is this going too far?

I’m in a relationship with some problems. i’m 17 and have been dating my boyfriend for 4 months. About a month after we started dating he cheated on me. I decided to leave it in the past and stay with him. then he started smoking weed and I asked him to stop because i don’t support it and wanna be with someone that smokes and he promised me he would. about a week after he promised me he would stop smoking I caught him lighting up again. and so this time he reassured me he was done for good. about a month later I find him smoking AGAIN. He told me he would stop again and as far as I know he hasn’t done it since the last time. Obviously I don’t trust him about anything he says or does (which sucks) But i’m starting to wonder if I should drug test him. is that just too crazy? I love him and I don’t want to end things but I also want him to respect me because I have done nothing to hurt or disobey him in the relationship. I really want to drug test him but I also don’t wanna seem like the “crazy girlfriend”