Most Helpful Girl
Her behaviour is very childish. Ignore child like behaviour or treat her like she is one. I would just stay very clear of her and avoid her at all cost like she is a plague.
Most Helpful Guy
Yea, move on its called relationships. You are going to go through a lot of these kinda games in life with the opposite sex, Males do it too, so its not just like women are the only one's.
Ignore her, do not give her the time of day, when she does something stupid look at her like she is stupid.
Best of luck.