Well, I've been told that women look at A's differently than men, but I don't really believe it. I also concentrated a lot on the OW's my H was involved with. They had rather poor characters, which, of course, I was happy to point out to him!! I believe he sees the truth now. He has also learned in counseling that he choose these women because he felt that was all he deserved -- he was dealing with a very, very low self-esteem and much feeling of worthlessness and self-loathing. Perhaps your W was/is having some of the same feelings.
I also confronted the xOW's -- the PA (almost a year after it was over) I confronted face-to-face; the EA, the day I found out about her I called her (she lives across the country) with my children and my H sitting right there! I also called the EA a couple of weeks later (after she contacted my H at work). I told her my H would be telling me of any contact that she tried to initiate because he was committed to making our M work and now wanted to be honest with me. I told her I had her work #, home #, home address, email address, her sister's phone #, and if she tried to contact my H again I would let the world know just what kind of a person she really was. I was also able to relate a few rather embarassing facts about her that my H told me so she would know with certainty that my H and I were on the same team now and there was no room in the locker room for her. Felt good. Bad DB'ing, but worked for me
So, my point is, yes, your W was/is going through "something." Of course, she picked a guy who was not worthy and a guy who would never measure up to you. A man like that wouldn't be sniffing around a married woman with young kids. Try to let HIM go. He's a scum bag who probably honed in on your W's vulnerablity at the time and took advantage of it. I'm certainly not trying to condone what you're wif has done, but I think we've all been vulnerable like that at some time or another. Some of us had the good judgment to say no. Some of us were just lucky that no one came around to tempt us at that vulnerable time.
I have come through this rather well, but if you'd ever care to read my whole story you'd see that it was an up-hill battle all the way. It took a lot of help from my friends here to keep me on track. Maybe we can do the same for you.