What is this girls problem?

She is a big time flirt and I know that she has got physically flirty with me many times before and when I added her on facebook she sent my profile link to a shitload of her friends. We were going to hang out for Ice cream but she couldn't go. Then this she almost completely ignores me. I really don't think she can think of me as a close friend I mean all she ever does is compliment me or flirt with me even talk about sex. I am 16 and she sits right next to me in my ceramics class but has been busy talking to other people. All of a sudden on tuesday she brought up a guy whos name she never mentioned when talking to everyone who sat our ceramics table. She said they were suppose to hang out on Saturday but didn't and I thought she might be talking about me. Her and her friends will never say the guys name when talking about it just seems weird. I was crushed when she kept talking about I feel so stupid and lead on. How the hell should I move on and feel better about my own self.