issue w/ bf smoking weed?

[baffled921]

i dont like weed, he loves it. i dont have a problem with him doing it every once in a while. i just dont want to be around him when he is high. he doesnt see why it upsets me and i cannot seem to explain myself. he feels that if i am not being physically harmed & he is not being mean/abusive/rude/etc. to me while hes on it, then there is no problem. my issue is that he changes. plus who wants to hang out with someone who is drunk/stoned anyway. everything about our relationship is great except for this one problem. how can i understand things from his perspective and explain mine in a way that he can relate to and respect?