(((Hugs))) I found it helpful to have a bunch of ready-made responses that were non-confrontational for times like this.
Like - "I'm sorry you feel that way." A phrase that I could spit out robotically, that didn't encourage further response from him & that might buy me enough time to just leave the room. If I couldn't leave, I tried to distract him by switching to a topic that was less likely to keep feeding his irrationality. "I'm sorry you feel that way. By the way - don't forget DD has a performance this Saturday at 5."