Do you own the home or rent? Whose name is on the home/lease? Is there somewhere you can go to that is safe? You should never allow someone to hurt you. He sounds like he is very volatile and you could easily go to the police and get a protective order. Why would you want to stay with someone who is so messed up on drugs and you are afraid of? It sounds to me like you do not have to do anything at all to engage him. You have tried to ask him to leave you alone and he refuses so how can you do anything to not engage him if he comes looking for you to instigate? No one can make you do anything. He cannot make you quit your job, babysit him or anything else.
Your best option is figuring out a way to get out of there as soon as possible. If you have no family or friends who would allow you to stay there are Women's shelters in many areas for abused women.
I hope you can leave this situation and do what is best for you.