Yeah, you should definitely talk to her. Right away, just sort it out. I made a mistake of not confronting on of my best friends when that happened, and we've just grown apart. We're still friends, but we're so different, it's very hard to keep close, she hardly ever tells me anything. Now we almost never see each other like we used to, and we're still in the same school. So you should just ask her, what's up...if the friendship means a lot to you, try to work it out, but if she's really changed a lot..well, it happens.