Hi Moominmommy,
You've had a heck of a lot to cope with...no wonder you feel like it's a huge struggle at the moment.
I'm on the autism spectrum. So are my family, and I work as an adviser on autism accessibility (though not on mumsnet - I'm here just as a mum same as everyone else).
Brilliant place to start is the National Autistic Society website www.autism.org.uk/ where there is a ton of info. There is also a helpline listed on there, who can point you to good local charities and services. There are often parents social groups etc where parents can support each other and 'let off steam' and share ideas.
Sometimes our behaviour can be worse for a while. Figuring out what's different that has caused it can take a bit of time, but it can be something that only we can notice.
Bit of background info about autism: (in case it helps) (all generalising, because we're all a bit different - but all of this has good research behind it)
It's a different brain design.
We're designed for fine detail, amazing persistence, incredible ability to notice what's wrong in a situation e.g. what's missing from a pattern.
We're ten times more accurate on work than other people.
We're amazingly honest about things and very loyal
We literally cannot see your body language - eye contact, face expressions, tone of voice etc is all 'invisible'to us. So we need really really clear words or pictures to tell us what to do or not do, and really really clear rules that explain exactly when to do it.
We're very routine-driven. We love things being just the same as they were last time. If things change, we panic. We need lots of notice of what's about to happen, so we can work out what to do and how to cope.
We do care very much about the people in our lives...but we're rubbish at working out how to say the right words and show the right expressions to prove it.
We often have sensory differences, so we can overreact to tiny unexpected things but underreact to really huge stuff. It's weird, but it's because of the different brain design. For example in a supermarket or school we can get totally overwhelmed by the amazing number of things to see, smell, hear, touch, etc and it literally hurts our brains so much that we want to scream or run or both. Social events do the same thing - it can be hell to cope with all the incoming social body language signals etc. It hurts rather than helps. So we play alongside people rather than with them, as it's less painful for us that way. We're not being antisocial.
Just some starter info. It's a whole new way of thinking, so it takes time to 'tune in'.
So many good people here to talk to.