How the hell do i leave him(PLEASE READ)?

Well talk to him about it. Tell him your worried about him doing drugs, and that you dont like how he treats you. Tell him what you just said. That if he loves you like he says, how can he like other girls? Tell him that isnt acceptable. If he loves you truly he will make an effort for you. See what happens, and if he wont change tell him you will find someone who will treat you right, and if he says ok, he never really cared too much so let him go. And personally i wouldnt tell on him about the drug use it will probably make him hate you...you could get him in alot of trouble if you tell the wrong adult...! good luck mssg me if you want to talk about it, ive also dated guys who did drugs so i feel ya..