Hi sandi, Boy, that's a tough one! But I'll give you my two cents.
First, I should tell you that I already DO know a lot about the affair. Lots of this from what was outwardly visible, and a lot more that I learned by snooping, back in the worst part of my sitch. I know many icky details of it, and I can say that I wish I didn't. But, that's from hindsight - if I did NOT know those details, would I still want to? So hard to say.
Next, here's my take on my own W's feelings about her A. She did this in the middle of a classic MLC, when she was depressed and lost. She built up OM into a romantic figure, then reality hit hard, and she eventually had to face it that she had pinned her hopes on a moody, obnoxious, self-centered a$$hole. (No editorializing there, eh?! ) So, she almost chucked her future out the window for THAT.
Today, I think her feeling about the A is lots of regret for a huge variety of reasons, from a huge helping of regret that she almost destroyed her family and her M, to (gulp) some very tiny part of her which regrets that she picked her OM so badly and regrets that it didn't work out. On top of that, add a really big helping of guilt and embarrassment.
I can only tell you what has worked for me in my sitch, and that was to let W dictate her 'terms' for coming back. In my case, that was to confess to the EA after it was over. The PA was never acknowledged, and I have never brought it up again. Because putting it behind her was what it took for W to move forward, with ME. I applied the test from Michelle, Will digging into the A get me closer to my goals, or push me farther away? And the answer was, I needed to move forward and let go of the past. I'm glad I did.
Thread #10 22 year M, MLC, Piecing since 1/07 Goal: Live with confidence & enthusiasm!