I really want her to be my friend, but it is not working.?

There is a girl that was in my cl last year and at first she really did not like me...then later in the year we became the best of freinds. So then this year I thought we would be the best of friends. I thought that the fact that we are not in same homeroom. Well I don't think that is it. She is trying to be in the popular clique, and I don't like the ppl in my clique and the ppl in her's do not like her. People tell her and she does not listen. The girl acctually came up to me and told me that she was DRIVING HER UP THE WALL. So I was thinking that it would be best if me and her just became the best of friends. There are so many things getting in the way like her parents are really judging ppl. So that is why I am freaking out because they might judge me by everything. So I was hoping that sometimes we will have sometime to talk like if she comes to my birthday party, then we can talk about this because this is not working out the way I thought it would this year. She keeps trying to fit in with the cool ppl, when they make fun of her 24/7 and she listens to no one when we try to tell her. She ever ditched her BFF just to be with the,(not me some other girl ). I don't know what to do because I think that I should do something to get her to be my friend.