I'm not! I promise!

She scares me. She's absolutely gorgeous and funny and knows how to manipulate people. She and I used to be friends, though she'll deny ever being close now that she doesn't like me. I just wanted to stay her friend. I don't understand why she changed. But she did, for the worse. Everything is about her now.
She's cheated on so many people. I don't understand why she'd do such a thing and why so many times. I don't know what drives a person to be like that, but I do know that humans are capable of repentance and change; she just refuses to do anything about it anymore. I want to be her friend again. I do, I'm just so terrified of her. Terrified that he wants someone like her, even when he tells me he doesn't. But then I think about myself.
I don't want to be anything like her. I'm an emotional person and sometimes I'm nervous that he'll mistake my emotions for just being a bitch and he'll leave me. I'm afraid he'll think that my need for physical affection (I'm a natural snuggler) is me being a slut. I don't want him to think my need to verbally rant my thoughts is gossip or slander. I don't want  him to look at my clothes and think, "She's a whore." I don't want that.
I'm not like her...I swear...