What is a lesson you feel you learned too late in life?

Helping yourself first so you have the resources to help other people and continue to grow and learn to improve yourself and don't let other powpl change who you are also most people will not give a *** about you . That isn't everyone. But as a whole in society somewhere along the lines people with mental illness are cast out as freaks of nature cause we're not supposed to be sad all the time . But ?