When you have thought it a healthier option, how did you detach from a situation?

It could be any situation of course. A family one, a circle of friends or a office filled with co workers. A lot of the groups I have just mentioned come with their own innate issues and dysfunctions. I am by nature a joker and love everyone to feel happy and relaxed. But of late I have found for e.g. my co workers to be slightly toxic.

When I withdraw from them, or settle down to work and don’t joke around, I get shocked responses, or surprised looks or hurt faces looking at me. I also get “What is wrong?” or “Are you OK?” Which actually annoy me then the whole situation is magnified.
I seriously need to detach from this lot and function in a calm and professional way without prompting them to ask all these questions and personalize it. How have you managed this in your own life successfully? i.e. successful detachment.