I read it more than once, and it still left me face palming. Everyone is acting defensive. Doesn't matter to me who started it if everyone goes off the rails.
Look at it like this: y'all need some de-escalation training. When someone misunderstands you, you can tell them without resorting to name calling. When you misunderstand you apologize. Not everyone is going to obey basic etiquette like this, that's a given. The only thing you have control over is yourself, therefore it's everyone's personal responsibility to not fall into a downward spiral that results in fighting.
I know we're better than this, so maybe we're just having a bad day. Egg nog, cookies, over-eating, and a short break are my strongly recommended therapies.