Lou hit it right on the head... Pussy whipped is more about a man doing things to please his woman, regardless of if it's for sex. And it isn't always about the woman controlling him. It can be... but if a guy starts dating a girl and tells his buddies, "Can't go fishing today, I'm having lunch with my girl." they are gonna call him pussy whipped. Heck, lunch might have been his idea. Guys generally use the term for harrassing a friend that's spending time with a woman instead of them. Sometime's it is because the woman is browbeating the guy into doing what she wants or because if he doesn't she'll withhold sex. That's my take on it anyway. And when I'm accused of being pussy whipped... I usually say, "Yup, and I'm getting laid tonight... what are you doing?"

__________________
Put me on wheels and I'll turn tricks.

Clever? Nah, I ran out of that years ago. But if you find this, let me know, k?
"The road goes ever on..." ~ Tolkien

In memory of my friend skip...
Go then, there are other worlds than these