LSG - All your feelings above I think are normal and very hard to deal with. I felt the same way. I thought I could end the A and control their R. I did expose and my H still denies (just friends he claims). I feel much better staying out of his A drama. Don't get me wrong I still think about it a lot. However, I have decided to let the A run it's course and make sure I'm the better option. I know the OW will eventually start nagging my H to not contact me, file, and commit to her. That will drive him away from her. I didn't trust that or believe it at first, but I do now. Letting go of trying to control the A has been the best thing I've ever done in my sitch.
I think you are doing very well considering the postition you are in, hang in there
Together 16 years Married 12 years Me 36 H 34 D9 & S6 Separated 12/3/09 Confirmed A 1/25/10 Exposed A 1/26/10 H hired L, but not filed yet 1/27/10