Im confused about my girlfriend, i can use some advice?? this is strange?

well long story short, there was a time that i was very obsessed with my girlfriend im not anymore i snapped out of it. my girlfriend is a manipulator, but now as im trying to break up with her she still calls and is being angry, she still tries to make me jealous etc... but she still calls me all the time acting like were still together. i dont call her she calls me. i just dont think she gets it. i thought since im doing the breaking up she should be nicer to me to try and get me back but shes still being a b**** does anyone know why?? and whats it going to taker for her to realize i mean business this time about breaking up?