I don't have any good advice or sagely wisdom to impart, I just wanted to let you know that I am keeping up with your situation and am deeply sorry for the pain and frustration. Just know you are among many of us who are going through the same sort of pain. It does have its ups and downs and I think you are in a down cycle.
Your wife is not going to confess. For whatever reason, they see no need to come clean and feel as if they owe you nothing. That would be too honorable and make things much clearer. I guess you need to ask yourself if you think that the A caused irrepairable damage or if you can work through it. For me, it is something I would not tolerate; it is a boundary.
Best,
--Chris
Me: 40 She: 31 S: 5 D: 3 Married: 8 years (05 DEC 99) Blow-up: 02 JUN 07 Piecing (More like Ostriching): 22 FEB 08