Do not inform your insurance unless you want your premium to rise whether you claim or not. You'll be seen as more of a risk. You may be better going down this route but think carefully before you do.

I'd seek legal advice, it is criminal damage so the police should act, and you should be able the reclaim back any financial losses from her through the civil courts if needs be.

Edit to add. Also get as much evidence as possible, just to prove its not an isolated incident and she is responsible for all damage