I've never thought of myself as a people pleaser, codependent, or one who is easily swayed by peer pressure. But the book When People Are Big and God Is Small: Overcoming Peer Pressure, Codependency, and the Fear of Man by Edward Welch is eye-opening in its discussions of emotions and our relationship to God and man.
One helpful phrase from the book that is worth memorizing is
"Need people less, and love people more."
When I am struggling with my emotions, I reflect on those words and try to change my focus. I should need God more than I need others. I should care more what God thinks about me than what others think of me. And I should be loving toward those who do not love me back (at least in the way I expect that they should).