This is a carbon copy of another huge thread here from about a month ago. You should read this thread as your scenario is EXACTLY what it was there. I will cut and paste a little for your convenience. This scenario is actually pretty common and proves that for some men we are sensitive about it. This is why women should pay attention and care about their sexual history.
Trying to understand my boyfriend - we have different views on past
My boyfriend and I have been together for almost half a year. Recently we started to talk about moving in together and getting serious. Yay!!! Anyway to make a long story short, he recently was told that I was with a guy he's heard of. That guy has a rep and it's not good. He asked me if we dated and I said yes but that it didn't mean anything and was for a really short period of time. Of course he asked if I slept with him. I didn't want to lie so I said yes but again emphasized that it didn't mean anything. He then asked why we waited a while to get intimate and again I was truthful and told him I thought what we have is special and really meaningful so I didn't want to jump into "things" quickly.
He just doesn't seem to get this. He sees it sort of opposite and feels weird. I don't know how else to explain it to him. To the guys here, is this how guys think? Also, to the women here, how can I better explain it to him? It's sort of started to affect us and I want him and me to be like before.
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This is a response I made on page 10 of this thread that got numerous thumbs up.
I think the lesson learned here is that yes sexual history does matter to some men, probably more so then women. Some of the female posters here shame men that it is an issue for using emasculating tactics. Everyone knows that women can get sex easily if they want it.
Katie doesn't sound like she is the promiscuous type but she made the mistake of having sex with some guy that her BF doesn't like or respect. I'm sure every woman here knows a woman that they can't stand that slept around and stole BFs from other women. I wonder how you would feel if you found out your current BF was one of her past conquests?
There was another 30+ page long epic thread here about a guy that found out his GF was seeing a FWB for the first 2 months of their relationship. The first two months they went out he got hugs and kisses when he took her out on dates then she went home and the other guy was getting sex. When he found out about it he didn't break up with her but downgraded their relationship to FWB only without telling her because they had never had the 'exclusive' talk up to that point and he refused to ever bring it up because of that.
If there is one thing that men cannot stand is being the 'beta' that goes through the long courtship process while the 'alpha' gets the action with no courting. This story just proves it again.