Leave him or keep him?

Okay I've loved this guy since 9th grade. He was my best friend in the whole entire world. We dated on and off for four years which is allowed concluding high school dating is a drag. He can be the sweetest guy in the world, but the biggest dick known to man at times. When I see him or hear him my heart basically jumps for joy it screams in happiness but he does stupid things. We began dating freshman year and a month into it he overdosed on benedryl. Yes I know that is ridiculous but he did. i stayed with him after he told me if I wasn't there he probably go back to the druggie life. He broke up after we moved dated two girls but cheated on them with me. He is a major computer nerd. Like Beyond hope. He wouldn't talk to me for three days because of WoW. He has to get to lvl 85. It hurts a lot and it is hard to explain to him these things. He doesn't really understand emotions well. He thinks crying is a sign of weakness so hedoesn'tt do it. He holds his head high and proud and will tell you your wrong. We have a tough love kind ofattitudee towards are relationship. We don't put up with each others bs and we will tell each other openly how we feel. I love him a lot and he loves me. We aren't together at this time but i don't know if I should just move on find someone else even though I love this guy a lot. We went through so much together ,and understand each other. We are best friend can tell each other anything but when we are in a relationship we are even better. i don't know. it is confusing.