So theres this hot girl....?

So im senior at highschool and there's this extremely hot girl that sits next to me in every cl. So i dont like her, I consider her more like my friend.So she is realy popular at school and some of the guys there made a rumor about me stalkin her(something i never did). So i like spoke to her and told her that thats ust a lie and that i have never stalked her. She told me it was ok but started actting wierd(she allready has a boyfriend, im not afraid of him, im way bigger and stronger than him but he is my friend and i dont want to end up fightin him).So anyway she has started speking less with me?wats wrong with her? why is she actting like that?any advice to end the rumor?