Heather Corinna replies:
You know, "slut" is both a really subjective and a really derogatory term.
A lot of people use it out of spite, because they're afraid of sexuality (or, more accurately, women's sexuality), and because they're afraid of people who enjoy it, and on some level, perhaps, secretly jealous. Not likely jealous about someone having sex, but about someone having sex and not appearing to be all worked up about it on the outside. On top of all that, most of the time women get called "sluts," it's got less to do with the women's actual sex life in question and more to do with how people want a certain woman to be seen in order to up their own power or social status.
Regardless, if someone calls you a slut for the choices you make, it's their problem, not yours. If you feel you've acted -- or may act -- in a way you're uncomfortable with, don't act that way. Hold yourself to your own standards, not someone else's.
Ultimately, my question to you is this: do you want first time-sex to mean something symbolic to you, and/or to be about a relationship or longer-lasting interpersonal connection, or don't you? Some people do, and some don't, and either approach is just fine if you're fine with it. If you do want it to mean something to you, then it's generally best to wait until it does mean something, until you're with a partner that's meaningful for you, in a relationship that's meaningful for you, otherwise you'll be grossly disappointed, and will probably be pissed at yourself for a good long while. Bear in mind, too, that if you're talking about vaginal intercourse, it's so physically underwhelming for so many women (especially those who have it with partners who aren't very invested in their pleasure) that for plenty, the emotional relevance is the big part of the deal, so again, just something to consider.
You might also just want to have a think on what having sex right now just because will actually net you, and why you're feeling this way. Is there a distance in your friendship because you and your pal aren't doing the same things anymore? If so, there are other ways to bridge that. Or, are you pitting yourself in competition with your friend, or being made to feel you're somehow lesser? Again, if so, there are not only other ways to deal with these kinds of issues, whether you have sex or not, you're going to still have to explore some of those other ways, because having sex alone isn't likely to fix them.
Sexual development and sexual life isn't a competitive sport -- it's your life, one that only you can live, and one that you have to live with. We all develop on different timetables. Some of the most sexual people I know didn't lose their virginity or become interested in sex until way late in the game. We aren't made better or worse by when we begin our sexual lives, but by how well we live them and with what level of personal integrity and joy.
If you simply want to get it over with because it feels like it's weighing you down -- and that's understandable, given how flippin' loaded virginity can be -- there isn't a thing wrong with that. Just be sure that's what you want, and be sure that you do so safely and responsibly, no matter what. The truth of the matter is that what may matter to your friend today probably won't a decade from now, because the chances are, you'll have different friends. But it's you, and your life, you'll always have with you.
Think for yourself, and make the sexual choices you make be about you and whatever partners you have, not about friends or other people you aren't in bed with. Figure out what you want, what is important to you -- and not based on competition or envy -- and make your choices accordingly.