How to reconnect with my friends?

Hi. I could really do with some advice. I'm not great with mending friendships (Usually friends make themselves scarce before things like this happen so I've never had to deal with this before), and I'm a little unsure what to do.

So here goes. This will probably be long.
TL;DR -  I missed a meetup with my kind and understanding friends due to intrusive thoughts and a massive meltdown, and I feel that I'm irrational for thinking my friend was dismissive. I don't know how to get past this. 

I have a little group of friends. Originally they were my twin sister's friends that she made in college, who were kind enough to invite me along to a birthday celebration so I wouldn't be alone, and since we all had some shared interests (things like anime, Pokemon, video games and fantasy, they even included me in their DnD games!), they became my friends too. Some of the group have drifted apart, but my twin sister and I are still very close to two of the group, we like to meet up often and I really enjoy hanging out with them. Meeting up isn't always as easy for me as it is for them, some activites that they enjoy doing are too overwhelming for me to participate in, I can sometimes get overwhelmed and stressed when we go out, and I prefer to meet up somewhere local so I can leave early if I really need to. But generally they are very accomodating, and I appreciate it very much.

One of my friends, S, is a real gem. I think he's a wonderfully kind person and I feel lucky to have him as a friend. He always reaches out if I've ever gone too long without saying Hi in the group chat, or helping me out with things like ordering food. However, something happened recently that makes me feel distant from him. My friend G is also super awesome, we don't talk as often but when we get together we usually have a cool discussion about some obscure topic, and I have a lot of fun hanging out with her. Both of them are lovely people, and they're so understanding about my autism, all the problems I deal with on a daily basis, they understand my obsession with dolls, don't judge me for my childish interests, weird fashion sense and social awkwardness. Which makes me feel so bad for all this.

We had planned a meetup a few weeks ago since we hadn't seen each other in a while. Unfortunately, on the morning of the meet-up as we were getting ready to leave, I began to have some severe intrusive thoughts. I don't want to share what the thoughts were about, but to summarise, I no longer felt safe enough to go out. Believe me, I KNOW how irrational it was in hindsight and I felt so guilty. Still, I reached out to the group while I argued about the situation with my sister, telling them I just didn't think I could make it. And while both of my friends told me it was okay, my friend S tried really hard to convince me to still come out. He promised they'd try and help me calm down, I could talk about any topic I wanted to take my mind off it, anything he could think of. But at that point, I was beyond calming down normally. I just couldn't do it.
I NEVER have meltdowns that bad, like EVER. I have had meltdowns, and could normally deal with it myself, but none of my usual calming methods helped. I felt so scared and overwhelmed that I just called my Mum at work. I don't do this, AT ALL. I have never called my Mum while she was at work because of a meltdown. She was an absolute saint and decided to come home early to help me. But still, I never made it to the meetup.

Here's the issue. 
S and G both reached out afterwards to check that I was okay, which I really appreciated. I told them the truth, that the intrusive thoughts had led to a meltdown so bad that I needed my Mum to get through it and ease the fear. G told me she was glad everything was alright, but I felt somewhat dismissed by S. It feels ridiculous and irrational, but the way he had pleaded with me to still come made me just feel worse. He had asked later if it would be worth talking to my therapist about ways to manage that meltdown without my Mum. And I know logically he was only trying to help and he understood why I couldn't go. But I can't help but be hurt. I don't ever have meltdowns like this, I don't want to have to make coping mechanisms just so I can force myself to go out when I felt unsafe. 
I know having autism makes me different from my friends. I don't think any of them are truly neurotypical, but my neurodivergence is to the point where my life has to function VERY differently from them. And sometimes I don't feel different. But this whole experience made me feel so... alien. It really made me view myself differently, and not in a good way. We're all adults, but I just don't feel like I'm an adult like them. I feel like a little kid trying to include herself at the adult table during a family gathering.

How do I recover from this? I love my friends and I know they absolutely mean well. My therapist suggested I talk to S and G about this one on one, particularly S, but I just feel afraid. I don't have good experiences with friends, and I'd hate to lose them. I just need to figure out how to feel okay with what happened. 

Sorry for the length, if you got through this, it means a lot to me. I just don't know what to do. I ended up going radio silent on the chat for weeks, but I know they plan to meet up soon-ish. I don't even know if I'm invited, but I want to be able to reconnect with them again. 

If you have any advice to offer, I would greatly appreciate it.