When is the right time to have sex with a guy, without setting yourself up to be called a slut and turning the relationship around to be all about sex? Because unfortunately this always happens to me. It kills my self-esteem!
Why do you get to be the slut? Um, the guy you're with is doing the same thing you're doing; why is it wrong for you and right for him?
But to answer your question: If you're really interested in a guy, it's best not to have sex with him for a good while, until you're sure the relationship is about you and him and not about your bodies. If you have sex too soon, everything goes awry. Often, you'll find yourself obsessing about a guy you really aren't that crazy about.
Develop a friendship first. Go to movies, have dinner together, climb the Empire State Building together if you want, but don't sleep with the guy. Don't assume that you owe him anything because he's graced you with his presence on three separate occasions.
Back to my disdain for the double standard (the woman ending up with the slut label, while the guy saunters off happily in search of the next mattress): It doesn't take into account the fact that women like sex. It's all about punishing her for giving into some guy when she's really giving into her own desires.
So you have desires, and you're entitled to them. He has desires, too. But his are not more important than yours. If you end up in bed together too soon, the relationship may end before it really started, but you are no more a slut than he.
As far as your self-esteem goes, don't wrap it up in some guy. If you think sleeping with him will jeopardize the way you feel about yourself, don't do it. Treating others as they would treat you is the best way to go through life, but make sure others treat you as you would treat them.
Would you sleep with a guy and then run around and tell everybody he's a total slut? Of course you wouldn't. So, don't waste another minute on anyone you suspect would do it to you.
To your happily ever after,