You need to be clear about what it is that's important to you in your life and express that to your boyfriend. My second response has to do with drug addiction. If you love your boyfriend so much, one of the best possible ways to help him is by setting limits. That might mean dumping him. If his drug use has escalated to the point where he has to be lit to have sex, then he has a problem.
Sex is a natural and normal function.
Getting aroused and expressing that arousal should happen without too much effort. If he needs drugs to do it, he needs help. It is one thing to do a little X once in a while and call it recreational. It is quite another to depend on it to replace foreplay. If you really want to have those peak moments with your lover, give him the phone number of Narcotics Anonymous or drug rehab, and tell him to clean up or you'll take a hike.