GIRLS PLZ HELP!!!!! she got a bf and wants to hurt me even more now?

Hi, the girl I liked got a bf....and she just goes with him in front of me and kisses him...that is obviously pissin me off...she knows I like her! When I told her I liked her she was nice to me for like a week. Then she started to completely ignore me...the she would try to piss me off by calling me by my nickname that she had stopped calling me after the week I told her I liked her. But she would only call me by it when she needed help on something...then she would get her hand and slide it down my arm when she wanted my attention for something...then she would move to the seat in front of me and put her hair in my face....this made me mad...that was thursday...then today I was for sure gonna ask her out but then she came with a guy and just kissed him in front of me...ust comes up to me acting like nothing ever happened and just started talking about she had broken her phone...then the teacher took my drumsticks and she just yelled out 'awww poor jorgie'...which is the nickname she made up for me....what is she trying to tell me....how can I get over her it rlly hurts why is she so rude PLZ HELP!!!!