"The Let Them Theory" by Mel Robbins

This is a compelling book, yet its concept is straightforward. All you need to do is:

• Stop trying to control others and accept their behaviour as part of their personal story, shaped by experiences and fears
• Say "Let Them" to stop trying to change other people or react to their actions
• Say "Let Me" to take responsibility for your own reactions, decisions, and emotions, and find ways to improve
• Balance "Let Them" and "Let Me"

All in all, "The Let Them Theory" leads to the hakuna matata type of life. Carefree, and, just maybe, free.