Don’t make a big deal about what they say. Showing them that you care what they think is only going to prolong the drama, which is what they want because it makes them feel important. They’re saying these things becuase they know you’re going to feel hurt. If someone hisses “SLUT!” at you in the hallway, you just whisper back, “I know! Aren’t I terrible?” and flash a wicked grin. I’m dead serious.
But you will have to behave differently – for yourself and to help you figure out what your sexual (and other) values are. More importantly, you have to think differently.
As for your behavior with the boys you had sex with, figure out why you did it if you feel guilty about it now. I hope you don’t. What’s done is done anyway, so you might as well ditch the guilt and move on. If it was just to have the experience or to have fun, well, there it is. If it was to fulfill other needs that you aren’t getting fulfilled elsewhere, like someone caring about you, then I would try to talk to a good counselor about how you can meet those needs without having to sleep with guys who have a good line and then gossip later in the locker room. Either way, I hope you protected yourself.
As for telling your friends your business, well, I suppose you’ve learned who aren’t your friends now. In high school, kids are gossips and very judgmental. We adults can see how hypocritical that is; after all, many teens are just barely developing their own values, so some kid talking smack about who’s slept with whom and handing out reputations really have some nerve. You don’t have to take what they say seriously. I know it doesn’t feel that way because high school is like a hermetically-sealed greenhouse where all sorts of creepiness spreads like tree rot, but you honestly don’t have to take what any of those kids say about you seriously. They’re bored/scared people trying to turn their mundane lives into a soap opera. Really.
So as long as you’re still in high school, you’ll just have to keep your business to yourself. Most high schoolers are too immature to be able to deal with talking about their sex lives the way most adults are able to do. As we grow, who someone else is sleeping with (if it’s not our bf/gf or spouse) really isn’t a big deal or anyone’s business.
As for salvaging your rep, here’s the other deal. People who talk that crap are either jealous that you behaved the way they’d like to, but are too scared to, or they feel small in some other way that they can put off and ignore by talking about you. So in the end, whatever they’re saying about you is really not about you at all, but them and their insecurities. Again, feel free to ignore them, especially if you’re otherwise just being your kind and lovely self.
Continue being the cool person that you are, go on about your business and ignore those haters. If it gets to a point where you can’t do your schoolwork or they’re treating you like the girls in the Judy Blume book Blubber treated Fat Linda, then you tell someone and get some help. Good luck. Stay safe. And ignore the haters. Hold your head up.