ERR-- On first reading the letter, I came to the conclusion that Dan did, that the primary problem was that the husband, a nice guy, was wronged. To believe this, we have to accept a world view that assumes women are the property of husbands, thus having sex with a married woman is doing something awful to the husband, that she's not a free agent in what happened.

But what if there's an alternative explanation, One that goes like this: "I really liked this woman. I dated her, took her out several times, enjoyed her company, had sex with her once, enjoyed that, was falling for her, and wanted to see her again with the idea that she would become the primary romantic relationship in my life. Then I found out that she was married, that she never liked me in the way I liked her; she was toying with me, using me for sex, always knew that the relationship could never go in the direction she implied! I feel like shit! What kind of woman leads a man on like that when she was married the whole time?"

If you tell the story with the sexes reversed, if it was a woman discovering that she's been dating a married man, you get a reaction like the one I describe above. If that's it, you tell your employee/confidante that there are dishonest people in the world and that the best you can do is vet people more carefully at every step in a relationship. That might mean dating alone at first, then dating with friends along so you can meet them. It might mean insisting on seeing where your date lives pretty early in the relationship. A true POS can figure out ways to lie and mislead anyway, but it can't hurt to do your homework.