I know this story doesn't really have a lot to do with marijuana, but I really need to get this off my chest. I'm hoping maybe you guys can lend some good advice. They started going out a little over a year ago and I always thought he was a good guy. I knew pretty much from the start he was an avid marijuana smoker and had been for years, and I knew how fucked up it can make some people (past knowledge from her ex-boyfriend). Months go by and I slowly become a smoker as well. My friends soon become his friends and we all start hanging out together (including my sister). They moved out of my parents house a few months ago and into their own place. Now with my parents out of the picture, I see the way he truly is. I'm not saying he is a bad guy, but when he isn't high he becomes schizophrenic. He calls my sister really terrible names in front of me and everyone else over NOTHING and later claims he was only joking or it wasn't a big deal. He'll instantly be angry at any of us for no good reason, other than the fact he hates his life while high. If he gets shitty with me for no reason I won't take his shit. Usually I'll just be like fuck this and leave before anything gets out of hand. Then, he'll go buy some pot, walk in an give my sister a big hug and kiss and apologize. Now, it's good that he apologizes, but he can't treat her like shit then expect her to forgive him just because he's happy that he has his pot. I'm in an awkward position because I feel like I should go off at him. He's 5 years older then me but I'm not really scared of him. The only thing holding me back is I don't really want to get involved in their relationship because it will just cause shit. My sisters ex boyfriend was like this guy x 10, he was a fucking psychopath. I won't go into details but we found out a lot of nasty shit that he did to my sister/family (stealing etc.) AFTER they broke up. I always knew he was a douchebag but I didn't know to what extent, and have always been down on myself for not doing anything about him when I had the chance. I don't want the same thing to happen with her current boyfriend. What would you do in my situation?