I doubt this is the case, but also consider this may be one of those 'little tests'. Some women are paranoid and suspitious, and often sign their friends up to see how their husband/boyfriend would reactto that friend making a pass. As I said, in all likelyhood this isn't the case, especially if you and your wife communicate well. But you never know.

I'd generally be like, "I'm flattered, but why are you even interested?"

Women tend to not like men who insist they're not attractive. It seems like they have confidence issues and that's generally too much to work with.

Or be like, "Well, I gotta say, I have this huge, festering pustule on the head of my penis that just WON'T go away, but if you don't mind that..."

If you can say it without wincing she'll run for the hills and never bother you again

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