My friends a wat do ido?

ok so like my friend shes kinda a and like i treat her like crap sometimes but then again i love her 2 death but shes such a ..let me explain what she does....okay she only likes guys who r taken so wat she does is she becomes friends with the girl that the guy is going out with only get closer 2 the guy and then she steals the guy away from the girl after she destroys their relationship wtf!