Judo

Judo means taking the force and energy thrown at you and using it to your advantage. Consider the applications beyond actual physical combat.
Someone spraying saliva while speaking-catch it in your mouth and spray it back. Body odor is met with airing out armpits. Burping triggers bigger burps as a response. If someone is talking fast, talk faster. Don't express frustration at slow talkers or people who take long pauses or repeat themselves. When it's your turn to speak, take longer, speak slowly, pause, repeat endlessly. Mirror the scratchers, except scratch in more places. Genital cupping is also easily imitated; throw in some rubbing.
Loud yawns, loud talking, loud farting, loud breathing, hiccuping, sniffing, yodeling, grunting, growling, anything obnoxious being tossed your way is grounds for retaliation in exactly the same mode. Lifestyle judo is all about anticipation and execution. There is no room for mercy. Telling a long unfunny anecdote or joke is robbing you of precious time and you need to address that with equal malice. Reversal from defensive to offensive should become a natural response to aggressive interactions. Age should not be a deterrent. Old people, once they get up a head of steam, can drive you out of the house with their etiquette attacks.
Sudden sobbing is the most insidious of power techniques. Your first response will be to sob louder. Instead, take a step back and wait until their initial burst has calmed down. Then, wordlessly offer the person a carefully folded handkerchief that conceals a gob of snot within.
This is about social survival and there is nothing pretty about combating in the mingle and mix pit.