My bfs mom hates me

So my boyfriends mom hates me and I don’t know why she claims that me and him spend to much time together but we don’t even live with each other only reason we spend every weekend together is because we both work and go to school. She is super controlling to him and even wanted him to install a tracking device to know where we were keep in mind we are 22 year olds , I was really creeped out by that and it’s taken a toll on our relationship mostly in the past few months . I know that he is her son but at the same time this is the man I want to marry. He will drop our plans to go to his mother no matter what it is and it upsets me because unless it’s an emergency he shouldn’t just ditch me. On top of that she gets made when we text and they are out together even tho she calls and texts him non stop when we are on a date. They treat him like a little kid and I love him to death but his whole family is so messed up they always fight when I go over and his sister is 18 and never had a job stays in her room all day his dad and him have a terrible relationship and his mom and him almost always fight about something , it pains me to see my boyfriend in this environment cause I care about him , I don’t know what to do I need advice on how to handle mother in laws :(