Let’s Waddle Together, Flipper In Flipper

When Co-workers do things like ask about weekend plans, chat about non-work topics, eat lunch in the same room, they are--subconsciously--reaffirming that they are part of a cooperative (or, minimally, non-antagonistic) social group.

The other primates cement social bonds by grooming each other; we do it by making small talk.

If they solicit your participation in these rituals, and you repeatedly refuse those bids, you are marking yourself out as, at best, an outsider to the group, and thus potentially antagonistic.

This is all happening on the monkey-brain level; they have no idea what they're doing or how they are interpreting your response, so there's no way to clear up the misunderstanding.

To the ape sleeping in your co-worker's DNA, either you are part of the grooming circle, or you are an outsider who, for all it knows, may be coming to steal all the bananas.

at some point, either in response to an invitation, or just in the natural course of conversation, you can add in that you are a "quiet type" who "needs their silence" or what have you. customize to your personal needs. i find it helpful to imagine a well dressed elderly woman describing the sort of peace she needs to manifest.

roughly once a week if you see a group of people chatting, engage with them. keep it pleasant. it can be superficial. word will travel that you are Nice and Quiet and Not The Chatty Type protecting you from group lunches etc. if you have an office with a door that you keep closed a lot, putting up any kind of decor will also send positive signals.

Example questions:

Did you do anything fun over the weekend? That sounds so nice! I had a pretty relaxed weekend myself, just [hobby] and a few errands.

Any plans for the upcoming weekend? [If yes] That sounds so fun! Are you excited? Going with anyone else? [If no] Same here, I can't wait to just relax at home! Any other fun plans coming up?

[Follow-up]: How was [event/hobby] over the weekend?

How's your [spouse/partner/kid/bestie] doing? Good to hear they're doing well! What have they been up to recently? Still liking their job / doing [hobby] / doing well in school?

Have you been doing anything new in [hobby] lately? Oh, that sounds so cool, do you have any pictures?

Read any good books lately?

Watched any good shows/movies lately? I don't know if I'll have time to watch that myself, but it sounds interesting. What do you like about it? [Note: this really hits if you don't care about spoilers. People love sharing enthusiastic spoilers. React shocked/excited then ask more.]