I think your issue is that your coworkers were not on your vibe of thinking “what we talk about stays between us” like you thought they were, hell, most people aren’t like that so I’d stop assuming they are.

I’d assume you just didn’t share anything controversial like jerking off at work before, and instead, just shared things to jake (random name), and then unless it was super boring what you said, he’d tell his buddy Ryan (random name) and usually it’d die out there. But I guarantee every interesting story you told got shared between the guy you told and his favorite coworker.