I keep reading all this stuff about how asd people have such low employment rates compared to other disabled people. Starting to think I'm on the scrap heap and will never work again. I wish I could go back and just do a maths degree. I need to find a job that doesn't involve people/office politics
Me too. This is actually my biggest source of fear and anxiety. I have never had a career. I did a degree and then drifted about doing waitressing and menial / factory work. Never ever had a clue how to choose or acquire a career 
Then I met DP and got pregnant - it was unplanned but I went with it happily - I think deep down I was glad, because now a path had been presented to me iyswim? Anyway, he got a job, we rented a house, a few years later we had DC2. And for a time I didn't have to make any choices. I would talk vaguely about retraining (but as what??) and getting a job (but what job??) once they were both in school, but it always seemed so far off!
Fast forward to now, and my youngest is nearly seven. I feel utterly frozen and incapable 
I just don't know what I can even do, never mind how to do it. Two years ago I did volunteering to try and gain some skills and experience. I lasted six months. I have obsessed since then about what went wrong...in fact it's part of what led me to wondering if there was actually something wrong with me. I could dissect at length why I failed, but would need to dedicate another post to it
Briefly, though, it was one day a week (that's all FGS!) in an office for an advisory charity. On the surface everything was great, I did well and was praised, people were nice, but. BUT. My anxiety built and built until I finally futzed and quit by email. I couldn't cope so I turned tail and ran. This has been sort of a theme for me - I did the same after two years of university - I'd been doing brilliantly but I just crashed after year 2 exams. I just told my DOS I wanted a year out or I would have to quit. It worked out OK and I did have a year out and did eventually get my degree, but not before I fucked up my year abroad (language degree) and was only allowed to continue with Honours because the department staff went to bat for me.
I mess things up and then ignore or run from the mess because I don't know how to fix them. It's like the running theme of my life 
Anyway, yeah, the work thing. I'm literally scared every day. I sometimes wish there was some kind of state-run work assignment department where they would run tests on you and just assign you a job that you'd be good at. "Show up at this location at this time and do X, Y and Z." 