Here is what I learned in the aftermath of Dday... I had no control over my fWW. The only thing I can control is me and my behaviors. I cannot completely control my thoughts or feelings. And feelings are not a good basis for making decisions, so don't make decisions based on feelings. Finally, at some point I have to forgive my fWW if we are going to move on and create a new marriage. We had to agree on shared values and shared boundaries. The key was agree, not dictate. If she could not do this with me, we would separate.
There are lots of definitions of forgiveness. The one I like is figuratively releasing my hands from her throat. It does not mean that I forget, or that we are "even" it does mean that I don't take it out on her anymore. That did not happen right away. Forgiveness was a practice that required me to say it and practice it a thousand times, and ask God to help me achieve it. But I did. It also did not mean that the scars from her infidelity went away. But my need for vengeance went away. My need for answers filled in that part of my heart. I became curious and I changed the way I asked or looked for answers. Slowly the shame that she felt for what she did and how wrong it was turned into guilt and her own curiosity about how she got there. How did she become a slut? (her words). Why did she need that validation? What created this terrible resentment in her that allowed her to do something so destructive. And finally, she started looking for ways to change these behaviors so she could be healthy and become the person she longed to be. In many ways, she had to shake that inner voice that told her she was never good enough. The voice that for a short time when someone was interested in her, quieted. Which is really why she had affairs, and allowed herself to cross boundaries that she new should never be crossed.
Early on, she could not get to empathy, because our approach to dealing with her infidelity caused her to go into a shame spiral. She would turn in on herself so badly, she could not even begin to see my pain. All she could do was collapse on herself and just try to follow the rules I set. It was not a marriage, it was survival. It was not love it was dependance. She could not become the person I knew she could become, because she was always in fight or flight mode fully in shame for who she was in her mind.
The only way that changed was understanding that she was safe, loved and cared for. She was not a horrible person, she had done horrible things. Inside that scared girl that would do anything to quiet the voice that always said she was garbage was a wonderful, warm woman that wanted to be accepted, but never knew she already was accepted. That meant that I had to change my approach from demanding answers to coming beside her and giving her unreasonable amounts of empathy and letting her know who the woman I fell in love with was worthy and not worthless. I had to find the strength to do that, but it paid off.
I am rambling. The long and short is that you need to ask if your pain is causing her to shame spiral. If it is, control what you can control, and try a new approach. If you cannot do that, end it. You are both in survival mode. That is no way to live. My marriage now is high fives and football games, climbing mountains, great meals and every once and a while, dealing with a little friction. But it is a marriage even she is proud of. We are getting to thriving. But we got there because I controlled what I could control.