Man, reading OIN's posts make me feel like were living the same life. Almost identical interactions. However, my situation is over. I got to the point where I had to make the decision to save myself. I wrote her a large cheque for some shared property(granted mostly mine), wished her the best, and changed my phone numbers. There comes a time, like Puppy, CG, TH, and Steve, when you have to put your emotional well being above your desire to save the relationship. I never got what I wanted which was a happy, healthy relationship with her but I got what I needed. I regained my self-respect and a sense of peace I haven't had for years.
I'm not in a position to suggest you give up on your marriage but I do feel like a different tactic is needed. You're getting some stellar advice from the vets, I hope you will at least consider it.
