I think I'm opposite of most guys.

I have always lasted forever with girls I just dated or random chicks. There were even a few that would make me stop after an hour, without me getting off, because they couldn't take anymore.

However, with my girlfriend now that I've been in a serious relationship for 2.5 years, 15 min is average, at best. There are just as many that last only 5, that last 20.

Its so much more passionate, and meaningful, and that's a huge difference than just hate fucking a bitch, or pounding the shit out of a girl that you know will run and tell all her friends, and boost your ego.

SO don't take it out on this guy. Perhaps he really has a connection with you, and you have an unrealistic view of intercourse length.