I like the "you won't ever be able to let this go will you" line. I think I'd probably reply one time with a laughing "I guess we'll never know, I never had the chance to try because you never stopped". Then I would never even entertain that statement with a reply again. It's like watching an interview of Charles Mansen on death row, he can talk for hours about religion and spirituality and the problems in society, and if you try hard you can almost overlook the fact that he killed a bunch of people. Craziness. And just like in his case imprisonment and death was the only option, when you have an individual that will commit serial adultery and then get nasty with you for not handling it the way she thinks you ought to...well, nothing to do but cut bait.
And no need to bring it up any more either. I hate to be negative but I seriously doubt this is going to change. It's been too much of her life for too long. Not to say it's impossible, but you certainly don't want to bet your well being on it. It's far more likely this is how she'll continue for the next 10 years as well.
Point is if she ever asks "is this what you want" or "is it too late", don't take the bait. She isn't seriously interested in R. If she ever temp checks you I'd just say "I'm not having this conversation." That's it. No more explanations. No more "I won't be in an open marriage". No more "I'd need a transparency plan". Nothing. Just don't have the conversation. Unless the conversation starts with her begging forgiveness and swearing to make it right, it's not worth having, and it's certainly not worth having if you have to tell her what words to say to string you along.
Sorry, I'm worked up just reading it. I'm not too pleased with your STBXW.
But the hard news is that it will still destroy your life. D is so brutal. Perpetrator or victim, divorce is the most destructive thing I've ever imagined. As bad as betrayal is, not having your partner to be hurt by is even worse. AT FIRST. But I swear to you it gets easier.
For those who wonder how it feels 2 years down the road, all I can say is that I never wanted D, it is the worst thing that has ever happened to me. It is painful beyond description. BUT. I can handle it. It doesn't define my life. It's one of those things I don't like, but can deal with. You can get there coffee, and whether you ever partner up again or not, there is no comfort to be found in the status quo.
Me:38 XW:38 T:11 years M:8 years Kids: S14, D11, D7 BD/Move out day: 6/17/14, D final Dec 15