Was he your "first" love? Was he the first guy you EVER really loved? If so, it might take quite awhile to get him out of your system. It seems that our first loves stick around longer than any other "love" we have just because they were our "first."
I've heard others say that their first loves always had a special place in their hearts years after they broke up with them. I sure hope that's not the case for you. LOL
You DO need therapy sweetie in order to stop the cutting! You were cutting before you met him, so you need to get to the bottom of what's making you cut in the first place. A good therapist can help you do that.
I wish you the very best. God bless and please take care. Hugs, Lee