Revenge isn't the answer; nothing good will come from it — Whenever you contemplate your actions, you should consider, "Will anything good come from this? Are these thoughts constructive or destructive?"
Revenge isn't worth it; just live your life and leave her alone — If she harasses you through social services again, consult with a lawyer and see if anything can be done about it.
If you lower yourself to her level, you will do a deed which you will regret and find yourself worse off through accountability — Revenge won't truly satisfy you and will create a thirst that cannot be quenched.
Take Care, With Love Through God and Jesus and The Holy Ghost,