Yeah...I've dealt with a few of these narcissistic nutters directly. One of the ways they win is by mortifying and shocking people with their behavior. That puts other people into a defensive, reactive posture, when they actually already own the turf in question (truth, reality, facts). But abusers like this and the number of people they can manipulate into being their groupies inspire people to forget, in the same manner that it becomes horrifying to lose "friends" because one of these conducted a smear campaign against you. Been there, done that, facts remain what they are no matter how much these people assault them, and they only become even more dangerous when we give in to validating their twisted bullshit. And responding as if we have new things to explain or prove or navigate about simple, old terms is one way of giving them power.

So yeah, the answer is to not leave the plausible reality to engage these people in their delusional one. The outrage they inspire is the bait.

In other words, maintain firm boundaries. That is pretty standard procedure for encounters with people with Cluster B personality disorders. They can tantrum all they want but you don't give in and start letting them call the shots about reality or what you will put up with.