Why do people think gay men are all cross dressers, and that they're weak, fragile and with a girl voice?

Maybe it comes from old negative media portrayals... or people who criticize pride parades. Who knows? But I don't know why the stereotypes just won't die... I mean, I always think everybody knows they're false, and then some straight person I know is like, "Oh, he can't be gay--he seems so normal!" or "Who's the woman in the relationship?" Arrrgh. Don't assume half-truths are true, especially when they're only true 10% or less of the time...