What is her problem, i did nothing wrong and she left me.?

Ok i dated this girl for 14 months. We loved eachother more than anything, or so it seemed. I put everything into our relationship. I loved her with every thing i had and i have no heart any more. we broke up four weeks ago and she is acting like a real....... *********...... and based on everyones opinion it is her fault but she contiues to talk crap. I didnt cheat on her i did nothing wrong, she told me it was because she didnt know what she wanted in life, then she tells all her friends a million differant stories, (cuz we argued *lie*, because i was to mature *always serious* fact is i kind of was but i joked around alot and made her smile all the time so.... and she said she has another guy so much better.) then two days ago she tells me i am a jerk and think i am stuck up, when i walk around the school with my head down all the time and i dont talk yea....... im stuck up huh....... then she says i am a constant lier..... i lied to adults so i didnt have to tell them why i am upset (its none of their buissnes so i make stuff up on whats going on with me at the moment) she lies to me about why she left, if she loves me, what is on her mind and what she is doing, TO ME. i have never lied to her and now she wont trust a damn thing i say. and to be a bigger hmmmm hmmm she makes her profile song echo- by gorilla zoe...... what is her fricken problem.... I gave her my heart and i didnt do her wrong and she is going above and beyond to destroy me....... WHY!!!????