There is this girl in my cl, help with her rudeness!?

It sounds like she feels left out and that someone has treated her bad. She doesn't seem to know how to be herself to get someone to like her. You're not used to being treated that way. Just be prepared that when you are around her again the same thing will happen. Think of a way to make her feel better about herself. Maybe tell her if she just was herself, she wouldn't have to be so mean.