DEAR ABBY: I am ashamed to admit this, but years ago I had an affair with a married man. His wife had no idea, but all of his friends knew about it. She recently left him because she met someone else, and he’s not only bad-mouthing her, but also using it against her in their divorce. Would it be wrong of me to help her by letting her know he was a big cheater? I don’t want to cause her any more hurt than she’s already experiencing. I no longer have any interest in him, but I think the information ...