I gotta say GAF, my life is currently in ruin. I recently discovered my wife had been having an affair with a coworker for 1.5 years. I found out, kicked her out of the house and we're probably going to get divorced. We have a 2 year-old (yes, she started an affair when we had a ~6 month-old) so it sucks even more.
This thread has made me feel a little better. I've been sticking to my guns about us being done forever but it's not easy...it's hard to let go even when you've been treated like shit. Good to hear that's normal.
Listen, that's rough and it's not going to help when I say that it's not unusual for someone to start an affair after a major life event. She may have wanted someone to tell her how beautiful she was (not that you weren't, but it somehow feels fresher and more meaninhful from someone 'new') and she may have been getting the attention that she craved from him.
It's not right, but don't make those huge decsions until you have talked it through. communication has to be the central issue here and if you feel your marriage is worth saving (even a little) then it's worth the effort. It might not work, but if you don't try, you can only know that it didn't. If you do try and it doesn't work at least you know that you tried.
PM me if you want.