Future in laws problems

My boyfriend and I live with his parents. I understand that it's their house and all but we literally have no privacy. They come in our room and go through out stuff. My boyfriend smokes and his dad always goes through his stuff and smokes it. It's so frustrating because we can't do anything about it. We're trying to get jobs so we can move but his mom basically tells him he can't move out we was going to leave but she went through and got half of his clothes out and hid them in her closet. He's 21 and I'm 18 almost 19. His mom is pretty much trying to force us to go to school and tells us we can't do anything without going to college.