As far as I'm concerned it should be a case of, who attacked first and was anyone killed? In which case it could escalate then into if the death was justified or not when the person defended themselves. For cases like this where you have these two people walking away unharmed it shouldn't be an issue, the victim should get help and counselling if necessary and the scumbag that attacked her should end up in jail.

As pointed out by this scenario though you can now see what deliberately vague law can do to a persons' life even by any persons definition they are completely innocent.