boyfriends dad

Me and my boyfriend were hurt in an accident and his mom was taking care of us, and his dad would purposely "trip" over our legs, or be extremely loud when we were trying to sleep or just down right being an ass to us by saying stuff like "there arms aren't hurt they can move, they aren't that crippled they can get it." 

He was actually getting mad that his mom was paying more attention to us then him. He thinks everyone's attention should revolve around him, and he starts fights over stupid shit. Like one day, I got paid, and he got mad that I didn't buy him weed, or junk food. He actually bitched to my boyfriend that I should contribute to the household more. But I buy groceries for me and my boyfriend like his mom asked. I help as much as j can, I didn't think it should be my job to pay for his habits. He also gets mad if my boyfriend or his mom gets high without him. He says they should give him some and shit. But he has his own that he doesn't share. It's fuckin bullshit. My boyfriend smokes weed too, and I sometimes buy him some, but I don't do it often. I smoke sometimes which is why I will buy him, but it's not my job to buy his dad. Both me and my boyfriend are getting to the point we can't handle it, but we can't financially support ourselves on our own. 

It's getting to be way to much. His dad is constantly yelling at everyone, calling my bf down, making him cry, which makes me feel shitty and like I want to yell at his dad but it's not really my place.