I need some legal advice, please help!?

Okay, I'm 20 years old and I've been living with my grandma for about a year going to college, i've lived here on and off my whole life. About three months ago she met a guy who she thought was just perfect, a month later, they married. No one knew anything about him except the guy that use to live with him told us all that he was crazy but no one listened... he doesn't curse and he acts like he's a big christian. Well, the other night out of no where he started screaming and cussing at me threatning to hit me. My grandma was scared, she didn't do anything. So i went in my room (it's an addition to the house that can be locked from either side of the door) and he locked me in my room and refused to unlock it. So, i went out my back door and around the house to the front door. He was in bed and i went in there demanding the keys to unlock my door. I picked up his keys and told him i'd put them back down if he gave me mine, two seconds later he jumped out of bed coming at me screaming ';I'm going to kill you god**** a**!!!'; I ran out the front door and he came right behind me about a inch from reaching me. My boyfriend recorded it on his phone to have proof incase he hurt me. No one in my family will do anything about it, they act like they don't care. I want to know if there is anything I can do for him threatning me?? And I would have left but i have absolutely no where to go and I think my grandmas too scared to do anything.





And he's also on depakote, hydrocodone, and god knows what else.I need some legal advice, please help!?
What the hell is wrong with you?! Call the cops!! File a formal complaint!! Do you realize that type of threat is actually criminal on a federal level! Please go to the cops immediately and press charges against him to the fullest extent! Hopefully once he is behind bars you can convince your grandmother to divorce him and kick him out! Damnit she can't be that desperate for a man!!I need some legal advice, please help!?
You need to talk to your grandmother about this and if she will do nothing to protect you then, unfortunately, you must move out. I hope it does not come to this. Keep out of his way.