@Carmen: My sister and I are the exact same way! We're not lesbos or anything, but I just dislike the drama about a relationship and its not even real. Its just something bored teenagers do, though sometimes they do it because they either think they are in 'love' or they're after something.
@Miranda: I agree with what Teal says, never ask that question, and when your friend put in: "...he won't say yes to you," was a sign that she was not okay with it. But wither she is or not you are allowed to ask anyone you want, and its her fault for not asking him first, as Teal mentioned.
Its horrible what's she's doing to you, and is obviously not your friend. The best action right now would probably just ignore her and laugh it off. If you show that you care she'll keep doing it and win, but when you show that you don't care she's only proving that she's a bleep and a donkey's butt to herself and everyone around her.
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Oh my gosh, I slept in today! And not just and hour or two of sleeping in, but I got up at 4:30 pm today! O_O