Title should be pretty clear, but story time nonetheless.

A few weeks ago I met a gorgeous girl at a party. The second she walked into the room, I honestly was floored. So, when she invited me to sit on her lap and drink wine with her, I naturally agreed. We spent an hour talking and flirting, and she told me all about being bi and experimenting with women. She sang to me in Gaelic, ranted to me about feminism - I was sold. We even made out in a treehouse and she told me how great my tits were. Basically heaven, right?

I noticed, however over the course of the night that she had been making eyes at a (male) friend of mine. She kept on asking him to come over and sit with us while she flirted with me. I, blinded by my instant crush, thought nothing of it. But, naturally, after we got back from the treehouse, he "pounced" on her, so to speak. They ended up spending the night kissing and cuddling, and I was left alone. When I talked to the friend about it later, he told me that she wasn't at all interested in women.

I recognize a large part of this might just be my own bitterness (and boy, there is a lot of it), but I can't help feeling a special kind of used. I tried to talk to her again at a party over the weekend, but she completely ignored me. Has anyone else felt like this before? How do you gals deal with being manipulated by the pretend "bisexual" women who are in it for male attention?