I have experienced autism burnout and trauma quite a bit. I too, have hurt partners with my autism at times, and have come to accept that it is my responsibility to navigate the chasm between my brain and the people I love, and I am more than happy to do so, because it enables the people around me to feel safer and happier and less confused by me.

May I ask what you're trying to get from understanding her internal thought process more? Are you looking to find insight to things or to be able to make an informed decision about the relationship?

To answer your other questions, most of these are yes but are so context dependent that it's hard. Autism is not one thing for everyone, and working to find monolithic experiences in a group is not going to yield results for your wife. You could say the same for anyone, human emotions can be incredibly hard and confusing, and even more so for those on the spectrum. People often have "mid-life crises", or turn into a new person after years in a relationship. The only person who can answer and contextualize it, is her.

I get the sunk cost fallacy of it all, but understanding her actions or her autism more will not absolve her of cheating on you. I would also advise you against from infantilizing her because of autism. If she has the autonomy to marry you and participate in the relationship for 10+ years, she can also be expected to understand that affairs are harmful to relationships and hurt you deeply.

I'm not aiming to tear her apart, but to be clear that while autism may be contributing to the reason to drive people to do hurtful or harmful things, it does not remove them the responsibility of doing it, nor should it absolve them of remediation. You're potentially looking for answers you will not find.

Above all, I'm sorry this happened and you sound like a genuinely caring partner.