It would depend if I was friends with my buddie's wife too how I would handle it....
If I was friends with him only, I would pull him aside and ask him if its worth giving half his stuff away and a life he has built....because women arent stupid, and his wife either knows or will know. He made a vow in front of God and his family and friends....
If I was friends with his wife and him, I would say that is a tougher call. I would have to say he should go home. That I wouldn't lie for him if his wife asked me what I knew, so it might be in his best interest to tell her.
I guess it comes down to character...
If this was a blip on the radar, and this was a good friend and not just an acquaintance, I would help him try and right the ship.
But character counts...and if someone is gonna cheat on their spouse, What will stop them from cheating a friend...friendship would be over.
I would be quiet about it. things like this seem to always turn around on you and make you the bad guy. The way I see it is if you tell, your going to lose 2 friends no matter what. If they end up kissing and making up with their significant others, they still wouldn't want to be around you so you lose the friendship of their spouses as well. Oh and I would get sloppy drunk so I could sleep better that night and not think about it!
__________________
Sometimes, when i'm lonely... i crawl into a laundry basket and tickle my ears. But, Some times I don't...
If I didn't do something about it, it would eat away at me. But at the same time, I'm not a tattletale either. I'd go up with them, chat, socialize, and then when I was alone with them I'd ask them what they expect me to do. I'd definately talk to them first before I would take it to their spouses, and it would depend on our conversation on whether I would tell their spouses or not.
OK, so the situation is that it is obvious something is going on? I would sit with them and talk it out leaning on my friendship to both. They've just been busted. My advise would be for both to do what they could to work out their marriages, but if they were committed to each other or there was no working out the marriages, end one thing before you start another! Even if you find escape or relief from your trouble by sneaking around doing something secret, you don't find a cure. Your problem is still there, and it will burst sooner or later if not attended to.