One of the best things I ever did to myself was work on my reactions and understanding my emotions, not only what emotion it is but why I feel that way. 

Mind Hacking Happiness by Sean Webb: https://a.co/d/8ars5wf 

Sean Webb's self map: https://mindhackinghappiness.com/wp-content/uploads/self-Worksheet.pdf

Name it, Tame it: https://mindfulness.com/mindful-living/name-it-to-tame-it#

More YourSELF by Sara Waters: https://a.co/d/6v1vRNj