He's someone else with his family (his dad) and someone else with me, what to do?

Yes my dear it seems like you are in a very messy and sensitive position and yes you do love your husband and wish him all the best. Here are a few thoughts:

Talk to him when it feels right: Perhaps you could choose a moment when you aren’t irritated and everyone you meet is not in a bad mood to cautiously explain to the person how you felt. Remind him of the fact that you want the old him back and question him how it feels to be with his dad. Each of you might get some information about what is going on.

Focus on understanding his experience: That could be true, but it seems like him and his dad had many problems that could shape his behavior now. It could be exploring that with a therapist, but if he’s willing to just talk about it, you might be able to listen.

Be kind to yourself: It is perfectly alright to lack ideas about how to support him and this could be as a result of battling your own difficulties. At least being there and letting people know you are thinking about them is probably more helpful than people realize.

Ask what support looks like for him: That is the thing you do not have to be an oracle, know all of it. Permission to question as in, ‘What is there that I can do to make it easier for you when we’re with your dad? Or what would be better in your comfort?”

Yes my dear it seems like you are in a very messy and sensitive position and yes you do love your husband and wish him all the best. Here are a few thoughts:

Talk to him when it feels right: Perhaps you could choose a moment when you aren’t irritated and everyone you meet is not in a bad mood to cautiously explain to the person how you felt. Remind him of the fact that you want the old him back and question him how it feels to be with his dad. Each of you might get some information about what is going on.

Focus on understanding his experience: That could be true, but it seems like him and his dad had many problems that could shape his behavior now. It could be exploring that with a therapist, but if he’s willing to just talk about it, you might be able to listen.

Be kind to yourself: It is perfectly alright to lack ideas about how to support him and this could be as a result of battling your own difficulties. At least being there and letting people know you are thinking about them is probably more helpful than people realize.

Ask what support looks like for him: That is the thing you do not have to be an oracle, know all of it. Permission to question as in, ‘What is there that I can do to make it easier for you when we’re with your dad? Or what would be better in your comfort?”

Thank you ever so,
I have tried to look back how it was for me when I was mentally unwell and despite my anxiety acting out differently or me not behaving like he does I know what we share in common is that super sensitivity. Bad things that has happened in the past that I before thought I was OK with and had dealt with returned to me. Suddenly they were way worse than they had been when I was well. I guess he's going through that each time he's not in a good place. He has to go through it the right way and I have to be part of that, doing my bit, us doing ours, before it's finally done with. I'm ready when ever he is. I've told him that now so many times I l have lost count. But he always starts something and then he drops it because he thinks he's fine or we're fine. It's like when we have to talk about something sensitive, he says few words, then he goes out the room and then he comes back pretending as all is how it should be, or just want to be friendly, make sure we are, and he can do this a lot, which means it takes time before it's settled and then I am the way I am and because of that it takes time too. I know he's afraid to loose it so I am confident that he will know when he's about to and that is when he leaves (and I always let him leave, I know he'll be back, he needs to be alone, I always still feel that he hasn't left me, I know he's thinking about the issue as much as I am). 

He reminds me of my brother (who too has autism, on the spectrum) in some ways.
That could be why I react the way I do when we're with his dad because partly it is this "guy-thing", my brother was effected by as well, (keeping things to himself, too much an introvert, still talking but not talking about what mattered, not with his friends, males, us something, was very wrong), I'm sure as it was with me he had no language for it, you just feel bad and not knowing why, the feelings paralyze you, but he got more and more that way. He was changing. 
Partly I can tell he's not OK the way my brother was not OK (before it got really bad), and first time my brother was like that I felt helpless and it really was as if everyone else around us missed the signs. But it was like they never knew him the way I did. 

Last I am afraid that he will be influenced in ways I don't want him influenced by his dad.
I don't want him to be jealous of me the way his dad is of his wife and as soon as we move or some small change is made they're on the alert.

I know I do this thing that I can think about wanting to do something only I don't tell anyone of my thoughts and then plans and then I go ahead and do it and it's all news to my husband then, to someone else I think they would just say OK that's fine, but he hasn't been "warned", this is going to happen, and I'm doing it, I'm not asking, I'm already on my way, and when I am it's difficult, if not impossible, to stop me. 

I have thought about why I do that and I think when I was a child I did not want anyone to stop me? But I'm someone who can exist in my own head and I simply have not thought about me having to tell anyone, like I'm on my own train, driving it, but forgetting there are passengers or they are waiting on "my train" and they don't know what's happening, and it does effect them. I've got to change that about me. He's done that too, presenting me with facts, and I too have at times reacted. I suspect he would be in a lot more trouble had he been with a woman who is not autistic (as I can in a way relate more). 

Been thinking before it was about him not being mature enough and that he would become so with age and being in the marriage with me and becoming a dad, but I think in a way we both were younger than our age, and where I know other people questioned why he was doing some things and seeing that as signs as if he simply was not mature, or raised differently, I knew for a fact he loved us very much and was very devoted to us. I was most likely more patient, but not even being aware I was that because in a way I was like him and in another I knew he did not mean it like that, the way I suppose NT close to us saw it as. I understood we would get the hang of it if people just butt out. I knew marriage was sacred to him and family and so I knew our place. He would get too obsessed about something when I simply finally had to put my foot down and at first he was fighting about it til he then understood he couldn't do that as much as before, it just didn't work with the life we lead now. Then as if he got scared he began doing too little of it and still asking if that was OK or not, as he was then afraid I would leave him. 

I don't want him to measure his own value by what his dad consider is man enough, as honestly all those "man enough" measurements are not, I believe, mentally healthy for any man.

I understand that his dad grew up under different circumstances and it has had it's impact. I know where he comes from were a lot tougher. I don't think I can even relate. 

I've told him they're superficial, the "man enough" stuff, they don't matter.
When I first started dating him he would tell me at one point that he felt crappy about something and I know some else told me to basically not date him because of it, but I didn't care, and I believed it would all work out, and it did.

 I would tell him what he felt crappy about that it was only circumstances and that can change anytime in life. I knew already then who he was and I couldn't care less.

As we went forward I could tell how he struggled, humbled, not saying anything about it, but really wanted to solve it.

He was more concerned with what my family and friends would think if he didn't solve it, and I didn't. I just felt if they don't love him because of this, because of a stupid circumstance, then they're the stupid ones. I thought But I'm the one who's gonna have him, what do I care what someone else think? They're not gonna have him. I am, if he wants me, that is. They can then mind their own business. (I too thought he don't know my family and friends, they would not act that way).

But with him it was as if he was surprised that my attitude was the way it was, that I never asked of anyone's approval of anything. To me that is just insane, is someone else going to decide what relationship I chose to be in or not? I don't take that kind of liberty towards anyone. To me it's as if a lot of people play that game and I never understood that. If he's civil or good to you than don't be mean to him. He already felt crappy as it was. 

Overall it's as if he always had had more concerns.
The way I see it father- and son's jealousy, them being worried, them trying to prevent something, anything, comes from a place of mistrust not only of the world, seeing it as more dangerous than I do, the people in it, us, but themselves, their own value, their own ability. They can act sure, but they can't be. Contagious. Influencing each other. It's that spiral downwards. I've felt powerless against it, just watching him, being that different, around his dad (or with the family when dad's around, his dad has that kind of presence). 

I've tried to explain to him that when he discovered that other guys were flirting with me that that too was in itself a different type of setting, circumstance, I happened to be in, I sure was not there for that reason, I was working, it was not as if on my spare time I would chose that.. I just happened to be somewhere where they began acting that way in a big way and it sure surprised me. I know for sure that if I am moving in with a different crowd, different people will be different towards you. This was a new kind of game and I was insecure and thought I was doing the right thing on my own behavior, acting right. He has said that he has never seen me flirt, but that I am nice, so he knows, he knows, I wouldn't do that. And these guys they found out about that too. They did not continue doing it. I'm sure I was not the only one they were flirting with, they were on a mission of their own. (I honestly think they would not dare to flirt with someone very beautiful and with a different attitude, I was not nor am I looking like that or acting). I've said I could have been the same way towards him as I too found him as much as attractive the way he felt about me. 

He will say stuff like if he looses me he will never find someone like me again, that he can't stand the thought of it, and that where he is now, what he's in, that kind of mess, that is the worst thing he can think of will happen, like that bad thing has happened, and that's bad, but if that too happens (if he looses me) then it's over, that he can't stand that, he won't survive that, or is afraid of those type of feelings, so that is where we now think it's coming from, the source, why he's starting acting this way now, "I can't loose you too". I can see now the warning signs he's expressed along the way before we got to this point after the bad stuff happened, that he's been afraid of that. I didn't get it then. Not why he was apologizing "I'm sorry I have to do this thing". Of course he did. I understood that. It had nothing to do with us. It's life. But he saw it as threats. 

He thinks I'm that rare (I think we make such a good fit is partly because he too is autistic, so we get one another, and he says he felt early on he could be himself and he loved that). I've asked him if he can imagine himself being with someone else and if he would trust her more than he does me, considering this is a problem he's having with me, and he says he would trust her less and that it wouldn't work.  But naturally he says things. One moment he says he does trust me, he knows I wouldn't cheat, but at the same time what he's up to shows he does not trust me all the way and he needs to honest with me why that is and how I can prevent it again. Some sort of trust has been broken. The past has too scarred us with me getting the way I got but even back then I wasn't cheating. 

He said he thought about it a lot when I was unwell because he felt I was not present and he felt he did not know from one day to the next if I was still in it (the relationship). He said he felt as if we were living under the same roof, but I was disconnected.

Then he felt hope, glimpses of me returning, to then retreating again to where ever I was (inside).

There were times when we would get into a fight and he said it was as if he was watching himself say and do things simultaneously that he knew was making things worse, but he said the thing was he wanted me closer to him, but he was going about it all the wrong ways.

At the time I understood that this was his past, experiences, how he had been taught too to be in fights (verbal ones), and that me behaving the way I did (as I was unwell, disconnected) I suspected had to do with his past too but I was responsible for my part but I was sick. Afterwards I have been told things, Do you remember that? Do you remember this? I don't remember. I have no clue. I'm just happy nothing bad happened. 

I think that with us he's got some % that it's because of his past, and then I do something wrong (without understanding I am, all the time) and am responsible for my % so then the past + me that gets to be "double trouble", in his head. I've tried to fix my part, all kinds of ways, at the same time I am effected by it because it too remind me of my jealous ex, as I don't want to get neurotic about what could cause jealousy or mistrust or not, as the slightest thing could and did, and then I tried everything I could to try to prevent that kind of reaction and I just gave up my rights and myself. I've never been that unhappy in my life.

With my husband's jealousy I am reminded by these old feelings I used to have and trying to prevent the same way, in fear that it could cause a reaction. I promised myself I would never allow myself to be in a relationship where I had to feel that, again, and become that woman again.

When I later got out of it and was back in my old shoes I could not recognize how I could have allowed myself to get to that place. I wanted no part of "her". It was as if I had gone under some black magic, become someone else during the relationship with the ex, and that I woke up from this bad dream. The ex did not get that I had woken up and he had lost all his black magic (really mental games, manipulation, his power over me and my own, fears).

At the time I knew I had to deal with myself, the fear I felt. I knew for a fact I did not love him and what ever he was saying he did not love me.
I do think behind his sure self he was deeply insecure. Sadly I think my husband is insecure too, not as much. 

I know he's a different guy than my ex, there are no cycles, not that kind of sickness there, but it's still this need to know everything, everywhere before it happens, when it happens.

With the ex I was terrified to smile or say thank you to a waiter (male) as I didn't know. He was cruel to me in ways that my husband never been. I did not tell anyone because you feel confused, ashamed, I could not sort out my feelings or thoughts. 

I don't know if it goes for all autistic males, but the ones I know they have to me this unique kindness to them, it's in their very bones.

They would not say so themselves, of course, but I can say it of them. 

I think my husband is the first guy I've met that's autistic (romantic kind of relationship), the others I haven't been in any romantic relationship with, but I can still say for sure they all have it, that same unique quality of kindness.  My brother sure has it. They wouldn't be able to get that way (the way my ex was). For what it's worth.