please some one tell me if this is fair.

So me and my boyfriend smoke weed. We aren't stoners, we just do it once in a while. Every single time I buy a bag I always share with him and only him. I only smoke with him. But every single time I buy it he take pics of the bag and sends it to his brother saying it's his. (His brother is a stoner) I also bought a bong last month and he showed his brother and said it was his and let his brother use it without my permission. His brother has also stolen weed from me, or at least my boyfriend says that he has. (Even though sometimes I think my boyfriend has smoked it with his brother) anyways. Every single time he gets weed he never shares it with me, always smokes it with his brother. So I get worked up like why do you always share it with him and not me when every time I get a bag I only do it with you?. He gets all pissed calls me a cunt says he hates me and that he rather smoke with his brother cause I always ask why he doesn't share with me? Even though I always smoke my boyfriend up. Just annoying how every time I get a bag he tells his brother it's his and then every time he gets it I try to hold the bag just to look at it and he says fuck off it's mine.