Read other letters about this article
Of course the BF is irrational about sex; everybody is. If people were rational about sex, they would not have any at all, what with all the diseases, embarrassment, heartbreak, and other assorted risks that are involved. It is the fact that sex is not rational that makes it fun.
I have been in a similar situation to the LW’s boyfriend. Many years ago a had girlfriend whom I cared deeply about and things were going swimmingly until, one fateful evening, we started talking about past (sexual) relationships and I asked a couple rather direct questions about her past experiences. She answered honestly and I experienced symptoms much like those the LW’s boyfriend reported; sickness and constant visions of my girlfriend engaged in activities which I have never done and never want to do.
Long story short, I couldn’t deal and we broke up. The lesson? (with the benefit of years of hindsight) I did not really want to know what she had done in her past. My questions about her past were irrelevant to my then-current relationship. I’m aware of my hang-ups. And, as someone already noted, she could not have gone back and “un-fucked” anybody.
The BF is not nuts just because he doesn’t like it that his girlfriend had a three-way, and none of the people writing comments have enough information to say that this guy is a hypocrite. Everybody has sexual hang-ups. His problems are 1) not being smart enough to realize that an honest answer to a question irrelevant to his current relationship may bother him and 2) not having the ability to either learn to deal with his girlfriend’s past or break up with her. Cary is right; the relationship is over. If he were going to get over it, he would have already done so. It is time for the LW to cut her losses.