I have this friend who is kind of self-absorbed and takes me for granted. What do I do?

Let's say I like a guy; of course, she has to like him too. And a few weeks later, she'll ask him out. She's uberly gorgeous, so most of the time, they say yes. And besides her asking guys out, they ask HER out a lot. Guys never ask me out; but they at least talk to me, when I'm around her. And she knows how I don't really like to shop at "Hollister" and "Abercrombie" and all those stores, but she buys stuff from there and acts a lot like the other girls that shop there; who aren't very nice to me. She calls me names, then says, "I was joking! Geez! You lost your sense of humor!" I didn't lose it. She's just calling me things I don't like to be called. Plus, she's "joking" a lot; meaning she says stuff she "claims" she doesn't mean. Despite all this, she's always given me great advice and been there when I needed her. But then I think of her problems, and am caught in the middle. What do I do?