Fallout!!!!!!!

im so confused?! so heres the background rite? me and this girl r really good friends. we flirt and everything and its just like we're goin out, but the relationship is purely platonic. its bin like it for the last couple of years now, but it gradually became more intense. (its not goin where u think it is!) bout 10 months ago she got a boyfriend and r relationship stayed the same but it annoyed him. it came to a stage where if i went somewhere with her it would have to covered up and if i fones her and he was there id have to be some1 else. then a couple of moths ago she split up wit him, and i was the first one she called in fits of tears. And she foundout he was cheatin on her, for a while with different ppl.
i dont know if that is relevent but neways........couple of weeks ago she got off with an old mate of hers , a brief ex, but i was the last one she told.
shes like the total A star student, and better than me in everything even the things i know im good at, and in some ways equal to her, like art and graphic design. i know it sound stupid but i spose it jus gets on top of you after a while always being overlooked. thn last onday i jus stopped talkin to her. i dont know why, i wasnt stressed with her or angry with her i jus stopped talkin, although if she talked to me i would respond. since then others have got involved and im being seen as the bad guy cos apparently im being 'nasty to her' . it got quite nasty wednesday with her friend slaggin me off and stuff.
i know i have friends who think ppl r reacting really harshly to me, but i dont know wot to do. i just dont feel like talkin to her. its like i dont even know her any more.i dont know if its the possibility of her gettin with some1 else again after last time, or i just feel like i have to move on. i dont know if i really am being the nasty one and out of order or wot to do.

help me!!!!

sorry it was a bit long!