He is smoking pot more than he used to, what to do?

My boyfriend of 7 months smokes pot. He used to do it occasionally but now he has been doing it almost on a weekly basis. At least once a week. He will be graduating and moving on to college after school and I still have a year left, and I am stressed that the time we have together won't be much after this school year. I know I am still young and maybe it is just "teen love" but I know for sure that this guy is very special to me. We have a lot in common and have a lot of the same ideas as well as the same wants from life. We are very good friends, and both treat eachother very well and caringly. I have a very strong attachment to him. We have never had sex yet as well. So with that said, I think we have something pretty good going for us. But what is worrying me is his smoking. I have never smoked pot and he knows I don't want to either. And he respects that, just as I respect his decision to smoke. But there is a line and I think he is very close to crossing it. Also, we have discussed how much he is smoking now and he is definitely aware of the fact that I don't enjoy seeing him get high so much. Our future is stressing me out a bit, seeing as I don't want to be with a pothead and I don't even know if we will make it through not seeing eachother much after school. On the other hand though, I don't want to leave someone of whom I have such a strong attraction and attachment too. What are your opinions on what I should do?