I'm sorry, buddy, you are seriously, seriously deluding yourself. Hello. You even posted an entire thread that is titled "You were all right, unfortunately." So then... we show up with some more advice... and you continue to argue and defend your W.
I don't get that.
The childhood story... I'm sorry for her. It does NOT in any way, shape, or form... justify an affair. Lonely feelings... being angry, sure. An affair? Because you weren't paying attention? Please. Most Hardware stores carry ample supplies of 2 x 4s.
You are 50% responsible for getting your marriage in a state that made one or both of you vulnerable to an affair (and I'm still waiting to hear from you on what you think your part in all of this has been). But when a person decides to take the step to participate in an affair, they are 100% responsible for those decisions and actions.
ALL the advice others here have posted to you comes from experience... and notice how it is largely the same kind of advice... hmmm... wonder why... maybe because... it's TRUE???
Your DB coach is right that since you have confronted, your W and your friend are probably going to lay low for awhile, and more than likely, get more secretive.
I'm glad you are willing to babysit your wife's morality and ethics instead of making her responsible for her own choices. That might even be part of the problem to begin with.