Welcome to SR
You are among many who have been in similar situations - please continue to read, post and search for what is your path.
as for what to do? Have you ever been to an Al-Anon meeting? Please know that these are not just meetings of little ole ladies sitting around talking about how bad their husbands are - if you get to a meeting that's like that - FIND ANOTHER ONE! (ha ha ha)
For me, meetings were great in helping me figure out what was best for ME.
It helped me get in touch with my Higher Power, calm my insides and clear my head so that I could make decisions about where my life needed to go.
No one can tell you what you need to do for you - You will need to make those decisions for yourself - we can only share our experiences -
Nothing changes if nothing changes -
You already know you can't change her so that means you can look at what you can change in YOUR life to make it better - doesn't mean you have to walk away unless you want to.
Don't give up before the miracles happen in you - You deserve it!!
HUGS,
Rita