We might get murdered

A restraining order couldn't hurt, but keep in mind that it's only a piece of paper. If he really intends to do you harm, a restraining order will NOT stop him. Remember, the cops can't throw the guy in jail untill he actually commits a crime.

I agree with the other poster, you may want to consider buying a gun of your own. Simply owning it isn't enough though, you'll need to learn how to use the darn thing. Self-defense is a serious matter, buying a gun isn't something you should do unless you intend to practice with it on a regular basis. It might be a good idea to have the girlfriend practice with it as well...

Jam it back in, in the dark.