Just found out

I have been where you are.  My experiences and observations may not fit your situation but I'll offer them for what (little) they may be worth.  First, other than gathering enough information to help you to determine how you might want to proceed, I would NOT delve more deeply into the intimate details of the one night stand.  Once you get started down this path, there is no end to it.  If you become a voyeur, it could haunt you and make your hurt greater.  I really don't see any positive outcomes to following that course. Second, you need to step back and see what your inner feelings are about what the one night stand really means to you, e.g., your values, your ability to ever regain real trust.  Trust is a fragile commodity.  Once lost, it MAY in some cases be a transgression that cannot be mended.  You may want to consider talking to a professiona counselor to help you get in touch with those feelings.  At some later date, if you see the realationship MIGHT be salvaged, you may want to invite your wife into the counseling or have her seek counseling on her own.  If she will not do this, I would personally move on.  Third, how has the realationship been with your wife since May?  Have you noticed any change in her general behavior?  Maybe it was a fling--irresponsible as it may have been--for which she is ashamed and remorseful.  You are in a difficult situation but try to look at the big picture here before doing something you will regret.  Take things slowly until you begin to get your head screwed on straight.  You may find that, should you do something precipitous, you will be sorry for it later.  Move deliberately remembering that the big picture is what really counts.  It will be hard to do but, in my humble opinion, it is the best course for you--and her.  I am genuinely sorry for where your wife's behavior has left you but that is where you are.  Godspeed.  Craig.