Dear Prudence: My husband had an affair. After I discovered the affair and my husband ended it, I wanted to let the other woman's husband know about the affair. I joined an online forum where people experiencing infidelity can offer one another support. Everyone on the site recommends telling the affair partner's spouse: They say the other spouse has a right to know and that it helps destroy the secrecy that makes affairs appealing. I agreed with that.

But my husband said the other woman's husband is abusive and would almost certainly hurt her if the affair came to light. I feel like he's defending his affair partner by telling me not to expose the affair. The potential for abuse is the only thing keeping me from contacting the other husband, and sometimes I think the abuse is a cover story to keep me from telling him.

I just discovered I have an STD, which my husband gave me. We are supposed to tell all of our sexual partners — for me, it's only my husband — about the STD. I feel now more than ever that the other man has a right to know. What should I do?

Prudence says: Let's sort out the public health aspect first. If your husband contracted an STD from his lover, then that's a pre-existing condition in her marriage, and you don't need to inform her spouse.

I don't know whether the abuse story is factual or not, but I have to disagree with the conclusion of your support group that the right thing to do is reveal all to your counterparty.

It would be one thing if your husband had an affair with a friend, you were now cutting the couple out of your lives, and you wanted the husband to understand why. But you don't know these people and you don't owe them anything. Messing around with the other couple will only get you looking at externals. You need to be focused on your marriage, your husband's efforts to repair your trust, and why things went off track.

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