As somebody in college, I'm surrounded by people who have a wide variety of how they handle their, well, sexual lives. One of my friends wears a purity ring. Another is waiting for the right guy. Another has no interest in an emotional relationship but still enjoys the physicality of two people being together.
And you know what? It doesn't change who they are or how much they're worth.
There's a lot of the Madonna v. whore complex going on lately, both in popular culture and in young adult literature. This involves having one girl, who is 'pure' because she hasn't had sex, earning the guy away from another girl, who isn't as 'pure' because she has had sex.
What the hell?
The state of a woman's virginity does not define her worth.
Sex is a natural part of life and happens at different times for everybody and, honestly, as long as the person/character is handling it safely, there's no need for your character to judge or mock them based on their choices.
From The Lizzie Bennet Diaries. Courtesy of Tumblr.
The Lizzie Bennet Diaries - a modern vlog version of Pride and Prejudice, handled by the wonderful Vlogbrothers - handles this issue well in a way that most young adult novels don't seem to understand. Lizzie worries about Lydia because her sexual habits (and all her habits, really) are part of a larger destructive pattern; she doesn't seem to do anything safely. However, it's made pretty clear that Lizzie doesn't mind the idea of premarital sex as a whole, or sex as a whole, or thinks that there's anything wrong with doing it safely.
Why can't young adult novels handle it this way?
TheFuckDidIJustRead, a Tumblr dedicated to commenting on terrible young adult books, has seen this issue crop up in a lot of books that have been popular lately. Other people have noticed it as well.
And the thing that makes slut-shaming in these books so terrible is that it doesn't add to the story. It just drives home an inane and socially constructed point that "popping your cherry" (which is a myth to begin with) is the worst thing that a woman can do.
Young adult authors, look at your life, look at your choices! It's fine for the boys in your stories to have slept with girls or even, on occasion, been admitted rapists -- Hush, Hush, I'm looking at you. But heaven forbid a girl willingly enter into a bedroom with a man and have consensual and possibly enjoyable sex? It must be the end of the world!
Perhaps this rambling doesn't make sense, and that's because, you know what? Slut shaming doesn't make much sense either. You wouldn't make fun of somebody for having a different religion, or choosing to watch different television or read different books. This is a life choice, and as long as it's not destructive or affecting others in some sort of way, who the hell are you to judge?
If you're more interested in learning about sex, gender and being okay with your body and whatever you want to do with it, I recommend checking out Laci Green's YouTube videos, and especially her video on slut-shaming.