Mentally dead... (Sorry for the long post. Please help!)

I had this boyfriend. He seemed perfect and he was and still is. I was on my period when the spring formal came along and I was really easily set off. Him and my cousin took pictures in the photo booth and my cousin showed me them. When I saw the picture where my cousin, Macy, and my boyfriend at the time, Sebastian, were smiling at eachother, I started to cry. When he saw me crying he walked home and called me later that night. He told me why he went home and I broke down. He said he couldn't  stand the fact that he hurt me and he went home and cut himself about twenty times. I told him to stop but he never did. He would cut himself every day because of me and I couldn't stand it. I broke up with him in hopes that it would make him stop. It worked. And my fear came true, he started dating another girl and she hurt him. He attempted suicide four times. He was broken. I was forced to stand by and watching him mentally die. His friend talked to me today to tell me some bullshit about "I made his whole family cry." I said "I told him to stop. That didn't work. Did he stop?" His friend said, "Yes. Why?" I then said," Then it worked..." When I said that I almost started to cry. His friend, Adam, went pale, and realized the truth. In study hall later I heard them talking. I started to break as I heard Adam say, "She loved you. She still does. She had to make you stop. She always loved you and she always will. Too bad you don't love her..." When I think about it I cry. He was always over protective, he wanted to know who I was with at all times. He didn't want to get hurt. Do you think I have any chance of getting him back? Will he start cutting again?? I really don't want to lose him forever, but I fear that I already have. I need advice before I break...