An important boundary for self-care is to mind your own business.
Notice where you draw the line between what is yours to work on or deal with, and what isn’t yours but you still deal with it.
For instance, at my day-job recently, I was part of an inter-departmental project. Someone in Dept A missed a deadline, and that meant I had to drop everything to work on the project to make up time and pass it on to Dept B so they could finalize it. At first, I was grumpy. Someone else being tardy was putting undue stress on me and I felt disrespected. Then I shook it off and decided to mind what is mine. Their being tardy wasn’t mine, but I had to deal with the consequences. I did my best in the quickest amount of time to keep the project moving. I didn’t dwell with the story of being disrespected; I disowned it, since it would only divert my energy and add stress to an already-stressful deadline.
The next time you’re feeling stress, pause for a moment and ask if it’s your business and if you need to deal with it. If a friend of family member is trying to embroil you in drama, that’s not your business and you don’t need to deal with it.
Draw the line and save your time and energy for your own business.