I would never say anything. Ever. Why be the one who wrecks his home? And then his mind might get to wandering...might wonder if maybe I did something more than flirt with his wife. Maybe I was intimate with her. Then he gets angry, and feels like he has nothing left to lose. She'll leave him and take the kids, his best friend wrecked his marriage...sounds like about as low as a man can get. And when a man gets real low, he gets unpredictable. He might have been your friend at one point, but not now. Now he hates you. And a man who hates and has nothing left to lose can do some terrible things...maybe to me and my family.
So I don't say anything, because my only job is to protect my own family. Even if it's from unrighteous revenge.
The other thing a good friend knows, is that his friend's old lady is off limits. Not just sex stuff, but even close friendship and talking stuff. All my friends are married. I've talked to their wives for a grand total of 20 minutes (that's about 8 wives) in the last 10 years alone. That's it. And the only reason that happened is because they probably cornered me coming out of a washroom at a summer bbq party and wanted to chat. That's when I shut down socially and ho-hum about having to go see if the wife needs help with the kids. I get the hell out of there. Who knows? Maybe my friend comes upon the two of us shooting the shit and sharing a good old laugh, as just as we do, she puts a hand on my arm...not in a flirting way, but in that way that women do with male friends that doesn't mean anything. But us guys think it means something. And maybe my friend does. And now he thindks I'm hitting on his old lady. He can't trust me. Stops inviting me over to his place...stops finding reasons to hang out. I lose a friend, and I won't even know why.
No good can ever come from hanging around your friend's wife. Ever. Shut that stuff down. If you put yourself in a position to be hit on by his wife, you're an idiot and deserve what you get. And if you do happen to have that line crossed (which is 100% your fault...you know how to NOT be attractive to women, so just do that), then you shut your mouth about it. It's your fault you put his wife (however unfaithful she may be) in a position where she feels she can be that way with you. You don't fix that problem by ruining his marriage. You fix the problem by avoiding her like the plague going forward.
