Try to unpack this. If she still shares custody with this ex then it's in the best interest of that agreement for her to include him in the kids' activities. Isolating him from the kids would give him cause to challenge her for sole custody. If the guy makes threats then it's time to call the police. It is a breach of trust to gossip to mutual friends about your situation. This is why both of you - and probably the kids too - should be in ongoing family/marriage counseling. It's normal to need someone to talk to but since it's egregious to burden friends with this stuff (and humiliate your spouse in this way) it's essential to have a professional involved. Everyone in this scenario needs therapy. You can't control what this ex does and doesn't do, but you can control your own environment by making use of the standard mechanisms for managing past relationship baggage and ongoing difficulties. It's just never okay to air someone else's dirty laundry to their friends. Save your marriage by finding the appropriate venue for discussing your grievances.