Heather
I guess you asked what unstable even bloody well means? I'd like to tell you that he'll get it out of his system, running off like this, because someone he runs into will tell him what a git he's being about it all. I can't guarantee that, but I know that's what happened with Remus. There's no way on earth he's going to be there for you without loving you, and if he does love you he's not going to run away from all this. His family's got to be saying the same thing, don't they?
In the meantime, you've got your parents here? Your dad at least, yeah? Talk to him. Let him rant on and on about how he'll go after the arse who does this to his little girl, so you don't have to rant about it. In a pinch, friends'll certainly do as well.