I know the feelings you are having. I know first hand.
My W is a survivor of sexual abuse.
I am not a health prefessional but I can tell you this. It does manifest itself in adult behavior and can have a profound effect on the personality and their ability to make decisions.
There is a lot of fear and pain they must confront. And it has to be their decision do to it.
Now your normal reaction to seeing someone you love in pain is to try to help. When that doesn't work and they engage in self destructive behavior then you try to control it. when that doesn't work we begin to get angry and resentful...
I don't know where you are but you know there IS a problem.
In no way am I suggesting that her beahvior is excusable. It is not.
BUT
There is a reason or at least part of the reason that you should try to understand. Knowledge is power.
You didn't cause this and you can't fix it Sigh.
She has been a victim and right now she feels (I am just going by my W on this one) she is a victim.
Of you and the M
That is why she is seeking non judgment and validation from OM.
OM is a predator preying on an emotionally unstable woman.
You have a most difficult situation. Probably more difficult than most.
Your W is not just a WAS.
She did not choose what happened to her. And you did not choose to deal with it as she is now your W.
BUT
You do choose what do to about it now. And she must choose too.
My thread is over in MLC if you are interested in looking through it.
I hope it may help you understand and help you make your own choices.
My goal is to some day be the person my dog thinks I am