Why am i still in love with him? (LONG STORY)?

ok well it started in november 2010 when he asked me out and at first we were really good together nothign was wrong i thought he was perfect and i had my first kiss with him at a school dance and then on facebokok there was a girl and they would flirt back and forth so one day my friend acted liek the girl over text and not knowing it was me he otl dher that he loved her but he couldent break up with me... that sam enigh ti go tback together with him because he sai dhe ouwl dchange an d he did.. for like a week and then we broke up again because he was making up lies and stuff so i said were done. of course we got back together.. and then we borke up again because he tohught i liked another guy and then he went out with my friend while he knew i was still in love with him and th3n we get back together a week later and we stayed to gether for a month .. and then he met this girl i call her heshe because shes realllly manlike and then they went out behind my back and they would ALWAYS flirt and hold hands adn facetime.. then we broke up agian and then he said he loved me adn couldent live without me and then we got back together.. then we broke up again in march adn then in april was the last time we brok up.... ok so this is the major part of the story he made me cry, flicked me off told me he cheated on me with 2 gilrs and told me he was goi gout with heshe which he knows i hat eher with a passion and when i cried he laughed at me . i punched him and he started fake crying adn saying i punched him in the kidneys and he lied to all the teachers balh blah blah soo kno whe and tthat girl are going out soo i still love him completely when it was bad it was pretty bad btu when it was good it was amaxing we had so many inside jokes and he was my first true love i still love him now even though he hates me... tell me why after everythig hes done everything hes put me through i still love him completely and my feeliong havent changed?