[steevyjeors]

For me, this is very situational. If it is a very good friend that I go way back with then I'm more likely to say something. If the friend is just dating and hasn't been in the relationship for too long, I'm more likely to speak up.

However, if I don't have a strong / longtime relationship with my friend and they are married, then it would take more than a hunch or suspicion on my part to say anything. I'd need something pretty solid, just out of fear that I could disrupt a normal relationship and possibly ruin lives when there's really nothing wrong.

Another wildcard is work. I'm not going to put someone's job at risk on a hunch. So if a couple are both working with me and I grow suspicious that one of them is cheating with another co-worker, I won't say anything unless I have difinitive evidence.