I would like to delete this thread.
IMO the pot is a dealbreaker for a few reasons. First you've discussed your discomfort and he still does it 3-5 times a week. If he had agreed to cut back to 3-5 times per month then he would seem to be making a compromise. And you feel disconnected from him when he is high, that's a lot of time to feel disconnected. He uses it for pain relief? Unless he can permanently eliminate the pain or learn a drug-free way to deal with it, he will always be using the pot or some other drug. Its understandable that you don't like hanging out with his stoner/slacker friends especially when they're high. Does he get along with your friends? Its fine for a couple to have separate friends but they should also have some common friends, either melding in old friends or new "couple" friends. But the real problem I see for you in the future is his lack of motivation, which is a classic side effect of pot use. You will continue to move ahead academically and in your career, while he will be progressing at a slow pace if at all. You may start to resent having to be "the adult" in the relationship. You will be at such different places in your lives that the love and emotionally compatibility may not be enough to hold you together.
Your question of "how do you think I can get over this aversion to pot?" is really the wrong question. The correct question is the one you asked at the end--" Am I just the wrong person for him even though our relationship is great in every other way?"
And the answer to that question is yes, you are wrong for each other--putting aside the question of judgments here (and FWIW, I am clearly on your side--I think there are a lot of reasons not to smoke a lot of weed, just as I wouldn't want to be with a person who drank a lot of alcohol) and basically the only reason I could see for doing it is for someone who really needed it for cancer or glaucoma. But the purpose of dating is to see if you are compatible with someone for the future--you have only been together 6 months and here you are twisting yourself into knots trying to force yourself to accept something that you really don't. I am sure that your BF is nice in other way, otherwise you wouldn't be with him, but you are fundamentally wrong for each other--not only does he some pot, which you are uncomfortable with, but you don't like the fact that he doesn't seem to have much ambition to finish school and better himself.
You will be sad for a while when you break up with him, but he will be happier with someone who doesn't mind the drug use and when you find another great guy who is ambitious and doesn't use drugs, you will be wondering why you ever wanted to stay with this guy.
It is not an inconistent position to say, 'I think X should be legal, but I wouldn't want to associate with anyone who does it.' Most people have that kind of relationship with cerain exercises of the First Amendment.
You seem like a go-getter with some smarts, getting a bachelor's, working on your master's, while he struggles to finish CC. I see that as a greater divide in your relationship, you setting goals and achieving them, while he doesn't have much desire to improve himself, his circumstances.
And, this may sound harsh, but I greatly believe the maxim 'show who your friends are, and I will show you who you are.' His friends are people that you wouldn't want to associate with, so you may want to consider if you really want to be associating with him, longer term, acknowledging that he has some very good qualities.
"...I have concerns that his habit makes him lazier..." You don't say lazy, but LAZIER--than he already is. "...All of his friends smoke pot regularly and also have limited education and minimum wage jobs..." So he has limited education, and a minimum wage job.
"...In short, his lifestyle is not the lifestyle I envision for myself...". Supportive and kind doesn't put food on the table, a roof over your head, or put clothes and diapers on a child. Much less be a good role model for a child. So, is this REALLY the kind of person you want to build a life with?