I talk to my ex for parenting issues too. I blocked his cell phone so that, a) I couldn't receive his texts and calls; and b) to stop myself from being just as nasty when I replied. He can still leave voicemail on my land line and we can email. I usually let them sit for a day or two before I check them and he knows this. He doesn't get a reaction out of me any more so he's given up. And I'm much happier with myself for not being so reactive.