Should I try to get my ex back or move on?

well it's a long story...I met my ex back in Jan of '09 on a website clld Yearbook. we chatted online as friends in Jan till late Feb. we exchanged #s & began txtn & clln eachotha till we decided to meet late Mar of '09. we were kewl friends, but he develop a crush on me. at tha time, I didn't like him like tht, but he liked me. he kept askin to take me out, but I would turn him down. he nevah stop askin me. by Apr of '09 I finally gave in & went on a date wit him. we became a couple April 23, 2009. we hadd a pretty good relationship throughout tht spring/summer yr. but then I felt I was only wit him becuz he was askin me to be his grl, nt becuz I fell for him. I felt obligated to be wit him, so I dumped him in mid Aug of '09. I started missing him & got back wit him in early Sept '09. I dumped him again in late Oct becuz we got into a big fight & he pulled me down on tha floor & I got scared. I hadd got anotha bf in early Dec '09, but dumped him in early Jan '10 to get back wit my ex. afta tht, I started to fall for my ex & things were doin well, till in Mar '10 I admitted to my ex tht I hadd cheated back in Jun of '09, but he cheated as well. he turned into a complete asshole & our arguments turned into fights & our relationship was colapssing. I left him again in Jul of '10, becuz I felt he was tired of my bullshit & couldn't go on. I started missing him again & we were in a complicated relationship in Aug '10 till Mar of '11. everytime we were about to be a couple again he would back off or dump me. I even caught him in bed wit some fat fugly *** Korean *****. we got into a HUGE fight in early Mar of '11 & left eachotha alone for awhile. I recently found out he got a new gf. he says he loves me & wants to be wit me, but he loves her(idk how becuz they just started goin together). some stupid ***** wit three kidds. I knw I hadd messed up badd & I knw in tha past I was extremely selfish, but I want to make it rite. I want to wrk hard to get him back. nw I got a new bf & he's jealous. should I try to get my ex back, or move on & stick to my new boo????