As what I understand is, she might dont know who the culprit until her friend got caught and she felt sorry for it. Anyway, she can pull back and cancel her police report by going to the police station and explain that she realy dont want to charge her friend. They will release her friend. Of course before doing that, she need to talk to her friend and make her feel sorry for what she did to her. This just my personal opinion from what you had explained above. Cheers.