Why do you think she did this? (Ex Best Friend Question)?

I had a similar situation like yours once . But i knew that girls would always start drama no matter what. One girl got jealous of me cus i had alot of friends and she really didnt but i would also hang out with her most of the time i never did Anything wrong towards her but then she got all of my friends against me . But i knew that she was trouble and i knew she was tryna get me mad and break down cus i didnt have any friends but i instead i pretended that i didnt care and eventually that got her more mad and i soon got my friends back cus they realized how fake she was so just stand strong . Girls will eventually start drama with you all you gotta do is act like you dot care :)