I just turned 20, and I'm still a virgin. I just have unrealistic standards. I'm picky. Whenever there's a girl who's into me, they're either not pretty enough, or we don't have anything in common, or they're drunk, or they're too young, etc. I could have lost my virginity to at least 5 girls by now, but I just wasn't all that attracted to them, and I want to make my first time something I can remember with fondness, not regret.
It IS frustrating, though.