Anxiety about mixing your friend groups
I spoke to Refinery29 about why so many people hate mixing their friend groups and what to do about it. Here's an excerpt:
Beyond the struggle of trying to get everyone to get along, Dr. Mattu says that we tend to code-switch with the people in our lives, meaning that we change the way we speak based on who we're talking to. In other words, the way you interact with your high school friends will probably be different from the way you talk to your co-workers. If you have a situation where you're bringing those people together, it's normal to be nervous — not only about how they'll interact, but how you're going to act around them.
Check out the article for more.