(edited after reading a comment response from the author).

I'm completely changing my original response to your essay, which was clearly misguided.

You gave a response to a comments about your essay in which you stated that you and your husband had been in counselling for a number of years prior to your decision to end the marriage. Had you stated that in the essay itself, your side of this would have come across in a far more sympathetic light, rather than creating the impression that you busted the divorce/Parenting Marriage thing out on him out of nowhere.

That said, I'd still say you should have given the guy a few months- time that probably would have involved him living somewhere else- to grieve, process, and make peace with the end of the marriage- and then brought up Parenting Marriage. And it might be more palatable if this were done in adjacent or nearby homes rather than in the home you shared as a couple.

One other thing to consider about how he has responded to all of this: your estranged husband might be assuming that you would be the one who would be more likely to bring new sexual partners in than he is- the man clearly has crippling issues with self-confidence and self-esteem- and perhaps he thinks you'd bring in as many men as possible simply to "rub it in" that you'd left him. That's how a wounded male mind can work in situations like that.