<human>: Can you condense the text into three sentences or less?

Hey everyone! My boyfriend(m20) and I(f21) have been together about 6 months.  It's been really great, and I love him a lot blah blah blah, everything else is fine so I don't need to get mushy.

The only thing that bothers me is when he smokes.  I admit that he doesn't do it a lot, and I'm not dating a pot head who smokes daily.  It's maybe every few weeks.  A lot of our friends do it, and do it much more often than him, and rationally I know that (besides being illegal) it's not a big deal.  But for some reason that I can't fully explain, it just **bothers** me.  

My bf is a highly intellectual and rational person.  We've discussed this several times and when I can't back up my reasoning with anything other than emotion, it's like he counts it out as being valid.  My feelings aren't empirical evidence so they can't be counted.

I really like this guy, and this is essentially the only thing we disagree on.  I'm probably asking the wrong demographic here, but is it **wrong** for this to upset me?  Should I just let it go?  Any advice on how to brush it off? I don't wanna mess up this relationship in any way, but I can't shake the feeling I get when it happens.
<bot>: I get upset when my boyfriend occasionally smokes weed.  I don't want this to bother me, or mess up our otherwise great relationship. HALP!