I am very sorry to read how horrible he is being to you. It's not an ideal situation for you, or for the both of you really.
Thinking longer term, how many years do you have until you would expect to retire?
Rather than working in a minimum wage job for ever, what can we do to help you find a job that suits you?
As soon as I read your updates, that you already have IT MSc, I tried to think about all the roles where being "nice" and "user friendly" are not required.
For example, have you ever considered software testing? I know I am pants at this, as if I try to test something, I tend to see what I expect to see. There are other people where I work who can be trusted to see what actually happens on a new piece of software. They are few and far between and work are always looking for more testers
Starting with the link that Lazydaisies posted https://www.specialisterne.ie/
I was curious to see whether there is anything similar in the UK. I did a quick google and found such a diverse set of hits, services for children with learning difficulties alongside specialist recruitment for ASD
I wondered whether this one might be any good Yes, it happens to be for software testers
http://www.autismworks.co.uk/careers
This more general one
https://www.ambitiousaboutautism.org.uk/understanding-autism/independence/employment
Another in IT again that offers autism positive work places
https://auticon.co.uk/careers/
I'm keeping on looking because I'm now interested in how to sort through the different types of offers ...
even though I am aware that there is a fair chance that you as the person impacted are in a much better place to evaluate the different options.
Having read your updates, I would say that your "DH" sounds as if he has some seriously non-NT traits 😀.
How about writing a 'killer' app ? What would it do?