Undiagnosed but unravelling

Hi, I'm new to posting here but have been lurking for a while... I am a 50-year old woman with a long history of depression and anxiety. Aside from that, I have generally managed OK, thanks to the steadfast support of my husband. I have done interesting work, and I have done dull work. Been employed by large organisations and small ones, and also worked for myself. We weren't able to have kids, which was a source of much sadness, but have become crazy cat people instead. I have never found social interaction easy, and more than one other person in the room feels like a crowd to me, but husband is an introvert too so I'm not made to feel weird about that.

I took a major wobble in my early 40s when one of my two younger brothers died suddenly, and the whole family went a bit off the rails for a while. Whether as a result of that bereavement or not, I found myself beginning to unravel. Several years on I feel I have gone backwards rather than forwards. My hard-won social skills have deteriorated, anxiety has soared and I am struggling with confidence in my work, even when I am getting positive feedback.

Although I have friends with varying degrees of ASD, most of them are male, and it had never even begun to cross my mind that I was autistic too. Then a year or so ago I read a profile of someone in the Guardian and I was appalled to recognise myself in it. The recognition didn't bring relief, but absolute horror that it was so b****y obvious AND I am the most ludicrously introspective person it is possible to meet, and I had totally missed this great big fact about myself. I could not feel more stupid, honestly, if you pointed out to me that I'd had a third leg for 50 years without noticing. And I am certain it is a fact about myself (autism not three legs): it makes sense not just of my social struggles but of long-standing sensory sensitivities that I have largely kept to myself. (I have had relatively few meltdowns as an adult, being expert in avoidance!)

Since coming across the article I have done a lot of reading and reflection, and learned a lot about women and autism. But although this helps me see how I got to where I am, I still feel out of my depth in the here and now. More so, in fact. I feel as though my carefully constructed adult self has just reached her limit and thrown in the towel. And I don't know what to do about it. I am nervous of speaking to my doctor about it; don't know whether a referral is even possible in my area, let alone whether it is desirable. Is there a way to rebuild myself more authentically and more robustly than before, without going down a formal route of assessment and diagnosis? Or is the fear of that just the last throes of my former self?

That's a loooong intro, sorry. But if anyone has any advice to share re the what-now, I would love to hear it. What resources have you found useful? What steps would you recommend?