Boyfriend's Psycho Ex

My boyfriend and I are just now getting our 5 year relationship on track after splitting up for a year. We both dated other people but around 6 months ago we found our way back to each other and things have been great. His ex was very spiteful and had him arrested twice on false charges, harassed him at his job, vandalized his car and harassed me (the mother of his son) and the mother of his daughter. She and I are seeking restraining orders against her. His ex has a son from a previous relationship and despite the advice from me and his daughter's mother he still seems to want to keep a relationship with this woman's son. I told him it was a terrible idea seeing as how her reckless actions could've put him in jail and away from our son and his daughter for a year. I don't want to see mean but I think he should cut off all ties to that woman and her family for good.