If she is nearly as crazy as you fear...at least enough to get a restraining order, I believe it will only be as good as the force behind it. Meaning you may need to consider having a gun and a concealed permit if your area allows it. I'm sure some are going to beat up on me for that, but how many times have you ever heard a restraining order stopping someone from being killed? In this case as in others, it could certainly be enough for her to wake up and realize how stupid she was being, but it could also push her over the edge.