Need advice? crazy situation with old friend?

Ok ive known this girl for about 5 years, we always had a strange on and off friendship, i guess we always seemed like an item, atleast thats what ive heard. we got close, but i was away at scho0ol for a time, she had wanted to come to the same school she said but she got back in an old relationship and aftr 2 years i left my school. she droppedher boyfriend..through or friendship we got in lots of fights over stupid things friends shouldnt be fighting over, i made lot off smart *** comments about her choices of friends, and we wouldnt talk for long periods of time. anyway, we got into a big thing i was drunk one night dont remeber saying stupid things to her i was being a real @$$hole....this wasnt the first time so i just said i guess she def doesnt want to be friends so didnt bother contacting her for months. then her ex boyfriend keeps bringing her up and how he hears from her that i like her and says i should go for it..so ater a few months(i know stupid) i wrote a heartfelt email telling her how much i like her, and how i was an , but by that time she started seeing someone else...so months go by, I see her at a party, she has an ear to ear smmile on her face staring at me when i walked in, i felt like she was in y area a lot like she wanted to talk but i thought it wouldnt be a good idea, i should back off if shes in a relationship because I dont want to just be friends again. So I sent her mabye one IM not asking for a response really just something silly, and dropped her a message on her birthday...so a year goes by since she started dating this other guy, and months since i tried contacting her and I see she blocked me on AIM ( i know because on my other sn it says shes online)..then a month or so later I send a friend request on facebook and its still pending which means everytime she signs on it always says 1 friend Request or 2 if one from another person...I saw her a few weeks ago, avoided conversation she kept coming around me again not saying anything, and we met eyes from far away and she gave me a big smile?!?!? i sent her a message a few days ago saying im sorry about the past, saying i want to talk 2 her but just wanted to avoid a big thing. she hasnt responded. whats with all of this weird behavoir? i still hvae feelings but have moved on, have seen a few other girls since, i still think about her, its not getting easier.why is she being so odd? does she hate me? When she blocked me i had not tried any contact beore months so its not like i was stalking or being annoying? what the hell?