You certainly have a lot on your plate here.
It does sound like your daughter may have learnt some aspects of her behaviour from her mother.
It also sounds like your wife has some serious mental health issues of her own.
I see you say she has been on antidepressants for 25 years...has she been on the same one all that time? If so, my first thought is she needs to be on a more modern one such as citalopram or mirtazapine. These are similar to prozac but newer.
Has your wife ever had counselling? I don't mean brief chats with the GP but in depth sessions on a regular basis to try and get to the bottom of her own issues.
It is possible that there is an autism "streak" (for want of a better word) in her but it far less likely to have been picked up on in her childhood compared to now, especially if it was mild.
Clearly this has started to take its toll on you too.
It won't help anyone if you spiral down into depression so perhaps the time has come to lay all your cards on the table with your wife.
I think you need to be straight with her and say what you have said here about why you are not sure you can continue in the relationship as it is now.
If she will accept help in her own right (plus or minus perhaps both of you going to Relate) you may be able to turn things around.
I think what is much harder is if your wife doesn't believe there to be any problem with her own behaviour and will not accept it.
There is no easy answer here but your daughter may fare better if you are happier and less stressed than if you continue to struggle in the marriage and become increasingly depressed yourself.
This is not an easy situation all round but I think your wife receiving more help in her own right (if she will accept it) would help move things forward.
If she refuses this and won't go to Relate (or similar) there is nothing to stop you seeking some advice and counselling in your own right to really help you think things through.
You can either ask your GP about this or try this website:
Just put your postcode in and it tells you all the counsellors in your area and what they specialise in. Then you can contact them directly.
A lot of my male patients don't like the idea of counselling but trust me, it can be worth its weight in gold when you are trying to sort through such major life issues. It really helps you unpick all the different things going through your thoughts and I would really recommend it before you make any life changing decisions as it will help you gain clarity over things.
I hope this helps.
All the best.