Finding out about the A helped me tremendously as well. My W was in MAJOR denial about the affair, and had seemingly even convinced herself that she wasn't having one. When I confronted her, with evidence, she crumbled. Completely fell apart as she realized just what she had been doing. Until that point she had been having an affair in complete secret from all of her friends and family and was living a lie.
Now my W is filled with shame, guilt, and regret. Am I happy about this. No, it kills me to see my W filled with so much self-hatred. But did it need to happen for our M to have a chance? Yep. An affair is the ultimate betrayal, and my W needs to own the consequences of her actions. I hate to see her going through such pain, but she has to go through that to truly heal and become a better person. And that would never have happened if she continued to live in denial about what she did.
This was all about a week ago, so I can't tell you if it has helped our chances at getting back together. But it has helped me finally detach. For the first time I realized that this whole thing wasn't all my fault and that my W wasn't some kind of poor neglected martyr (which was what she was going around telling everybody and probably believing on some level herself). I also realized that no matter what happens, I can hold my head high. I have done the right thing, the honest thing, while my W has gone down a path of lies and betrayal. So the question is no longer just "Will my W take me back?" It's also "Will I take her back?" Right now the answer is yes, but every day that goes by without her recommitting to trying to make this work is a day I get closer to shutting those doors and moving on.
And, like Puppy said, it helped me form my strategy, helped me know I wasn't being paranoid (this is actually a HUGE mental relief and cannot be underestimated), and helped me learn OM's strengths (which are few) and weaknesses (which are many).
Me: 33 WAW/MLC: 33 M: 4+, T: 10+ Separated: Nov 08 A#1: Oct 08 - Jan 09 (exposed and ended) A#2: Feb 09 - ? 1: http://tinyurl.com/mrmistakes 2: http://tinyurl.com/ckch9t 3: http://tinyurl.com/stillwaters3