Steve85 - Thank you for the long, in-depth responses. One of the things that has weighed on me since the BD was that when I had a PA and depression-related problems 10 years ago, she was willing to work past that and focus on us, even though I had stepped out. After 20 years, I feel like I at least owe her the opportunity. That having been said, I do agree that perhaps she shouldn't be given the impression that our marriage is a revolving door.
This ONLY works if the cheater is sorry for what they've done, want to save the marriage, and are willing to work on the marriage. I can guarantee you that if you wanted to continue the PA and potentially make it a LTR with the AP, what your W did would not have worked.
So can you say she is sorry? Does she want to save the marriage? And is she actively working on the marriage with you? If you cannot say yes to those three questions (and "I don't know" is a no), then you approaching this the way she did when you stepped out will not work. There may come a time when she is sorry, wants to save the MR, and is willing to work on it and then you can give her that opportunity. But doing that before the answer to those three questions is yes is futile.
M(53), W(54),D(19) M-23, T-25 Bomb Drop - Dec.23, 2017 Ring and Piecing since March 2018