sounds like a desparate situation, i hate to make a snitch suggestion but have you consulted her mother yet (the evil little girls'), if you have and shes done nothing report it to the local authorities, i think its illegal to try to light someone on fire, and if nothing can be done fight back, if she so happens to lie a finger on you, if all else fails, give her a warning, give her a second warning, then you act and end it for good, make sure theres a witness and evidence that she struck you first though so you don't get in trouble with the american justice system (AKA 'juvi') but just go to her mother first.