"I went on a weekend trip and didn't invite friend A, so I hope friend B keeps it a secret and doesn't tell anyone I was there" is the kind of social dynamic that people grow out of in high school. If you are having trouble with it as an adult then it isn't really Instagram's fault. People talk to each other and share stuff, and sometimes they talk about you, both online and offline. Just live your life without being…
It's absolutely the fault of the mechanics and submission of our society to surveillance capitalism, one which has been intentionally cultivated, exploited, and capitalized, by Meta, so yes, it is Instagram's fault. They are the primary party—though I do not excuse those complicit with surveillance capitalism, meaning every person who continues despite unending evidence for how sociopathic and destructive the company…
Rue the consequences of making working for Meta socially and career viable at leisure. Maybe in an El Salvador prison.