Someone I know has been seeing a married man - wasn't much in the way of sex I understand mostly friends with kissing and touching (but she's not the first, and he's had a full scale affair before and admitted it to his wife!). His wife doesn't know about 'the friend' and they've been friends for several years now and work for the same organisation, and I know there are rumours going round.
I don't know the wife at all but am wondering if I should somehow let her know.
My ex-husband cheated on me for years and I was really cross people knew and didn't tell me, as I felt so disempowered when I found out, but is it the right thing to do, and how would I do it?