The scene isn't over. I wouldn't pass judgement on it yet. If the last page is something to go by, the author may honestly be trying to adress the problems in Alison's attitude. Let's wait and see.
EDIT: Reverent-One, right of self-defense does not cover situations where there is no immediate risk of physical violence. Miles was not violent, so Alison had no right to be violent towards him. Even a normal girl punching him would've been illegal, even though it would've been extremely unlikely for anyone to pay attention at that.