Would you tell?

I would tell the one being cheated on. It's their right to make an informed decision in their relationship. The person being cheated on may also have health risks they have a right to know.

As much as I hate getting into other people's business, I would most likely say something. If the situation was turned around, I would really like someone to tell me.

^^^ This

That would be extremely situational.

I guess it would really depend on what your relationship was to the couple. To me that's just not a situation I would want to be caught in the middle of, especially if you are friends with both of the people.

That would be extremely situational.

This. If's my best friend, of course. If it's someone quite removed, I am not sure I want to go and the be the one who starts that **** storm.

There are so many variables. Who am I closer to? Was it a "legit" mistake? How serious the two of them are? All sorts of things.

Bottom line is, it's none of your business what someone else does in their relationship. Unfortunately I learned this the hard way and nearly ruined a very good friendship.

If you feel like you MUST talk to one of them, speak to the cheater in private. Do not tell the cheatee and definitely don't tell others in your circle of friends. Look, I hate cheating like nothing else and get very upset if I hear someone I know is cheating on their spouse/partner but it's not worth the stress and upheavel you'll go through if you get in the middle of it.

ETA: That is a good point above about why most people feel like they should tell the cheatee about the cheating. And like I said, I get it. I personally can't stand being around cheaters. Took a break from one friendship over it and have ended other less worthy friendships over it. Cheating is a sneaky underhanded thing to do, especially in a marriage where you've VOWED to be faithful to that person in front of your family, friends (and most of the time, the church/God). So cheaters aren't just lying to their spouse, they're lying to all of the people that were there that love them and their spouse. Shameful...

I wouldnt tell. Not my business.

One of my besties has been having affairs quite a bit. Although I do not agree with it and feel bad for her spouse, I do not feel it is my place to judge or say anything. It is her life and whatever happens...happens. Karma can be nasty and those who choose to do things will have to face the consequences. She is my friend regardless and I will not rat her out or judge her for her decisions.

In the meantime, she puts her husband at risk for STDs, embarrassment, and heart-ache.

^^Exactly.

This again!!

And there is never a "legit" reason to cheat. Someone is in an abusive relationship? Walk away. Someone is already being cheated on? Walk away. Don't cheat.

Also- if you don't tell, and some how the cheated on finds out- how do you think that will bode for your relationship?

One of my besties has been having affairs quite a bit. Although I do not agree with it and feel bad for her spouse, I do not feel it is my place to judge or say anything. It is her life and whatever happens...happens. Karma can be nasty and those who choose to do things will have to face the consequences. She is my friend regardless and I will not rat her out or judge her for her decisions.

In the meantime, she puts her husband at risk for STDs, embarrassment, and heart-ache.

^^Exactly.

This again!!

And there is never a "legit" reason to cheat. Someone is in an abusive relationship? Walk away. Someone is already being cheated on? Walk away. Don't cheat.

Also- if you don't tell, and some how the cheated on finds out- how do you think that will bode for your relationship?

I'm not suggesting you tell. I'm suggesting you quit referring to a perpetual cheater as your bestie and get some new friends that, perhaps... deserve some respect and a loyal friendship. Because she doesn't.