I don't like this girl in my friends group
Let's say I have this 'gang' of 7 girls in my class. There is one girl in my gang who also join the same organization with me in school. But when we are in a meeting of this organization she treats me like I'm a stranger, sometimes she ignores me and prefer to talk to another friend, but when we are in class, with my other friends in my group, she treats me like I'm part of 'her' gang. Honestly, I don't really like her personality, she is kind of selfish, when she talks she wants to be listened but she doesn't listen to other. She is also an attention seeker, she always talking so loud and I can't stand her.
Here are the things why I don't like her:
- In our class, me and her, are the best because we always get high scores in every lessons. One day she said that she got a bad score but she didn't want to tell me what she got. But she wanted to know about the other scores. So I was kind of mad.
- We 7 planned to go on a trip together, we have prepared everything, date, hotel and transportation. Suddenly 3 weeks before we go she told us that she wouldn't be able to join the trip for some reason that she couldn't tell to anyone.
I mean as a 'best friend' there is nothing wrong to share about her problem, right? she made us worry, but she still doesn't want to tell us why she couldn't join the trip.
Beside she always ignores me in organization, I really can't stand her and would like to avoid her but I can't because it would break this 'gang' and I still want to be friends with the other.
What should I do? or maybe there is something wrong with me?