You have to respond in order to prevent him being able to say you won't communicate with him about the kids. But don't respond to every little bit of the message, don't get sucked into an argument. Just brief, calm, short answers. No snark no negativity. Don't get sucked into defending yourself, just answer matter-of-factly.
Last edited by job; 11/11/1607:40 AM. Reason: Corrected a word for poster "factly"