So I have a girlfriend for the first time ever. It's great. She's awesome and beautiful and we're doing well. It's fantastic. Among other things, I'm having sex for the first time ever. It's so much fun. But I think I have some sort of cruel and unusual psychological problem. Intercourse kills my erection! Let me repeat that. We start fooling around, we both get warmed up and ready to go. She's wet and I'm hard. Then we start. And just like that, my erection starts to fade until I'm completely limp. This is during the freaking intercourse! What the flying hell? I don't blame you for thinking to yourselves "Maybe you're homosexual and don't realize it?". Over the years, I've seriously and honestly considered it. But I have determined that I'm certainly straight. I'm almost completely a zero on the Kinsey scale. So I suspect it's something else causing it. Over the past decade of being sexually active, but without a partner, I've spent alot of time masturbating. The first thing I noticed as I was in the middle of losing my virginity one night a month ago was that it didn't feel as physically good as I thought it would. Don't get me wrong, sex overall is far more enjoyable! Far, far more! But I think I've become so accustomed to the way masturbation feels, and I've become so good at it, that the real thing doesn't seem to stimulate enough to feel as good. I don't like this problem. What can I do?