Jenn,
The first thing that came to mind was something that Dave mentioned about getting together with some of your neighbors about this. You can't be the only ones in your area that are upset about what's going on? You know the old saying about there is power in numbers. Well, if there are enough neighbors who have had enough of the kids's behavior, you should be able to do something about it. You could put pressure on the police to respond, go and talk to the kids as a large group, any number of things. I am afraid that if something doesn't get done soon, someone there is going to get hurt very seriously. And if this is pushing you to the point where you want to self injure, then it's gone way too far as it is, IMHO.
I hope you figure out the best thing to do, and please let us know how this works out, OK?
((((((((((Jenn))))))))))
Greg
"Beauty is truth, truth is beauty - that is all you know on earth, and all you need to know"