In displaying the psychology of your characters, minute particulars are essential. God save us from vague generalizations! Be sure not to discuss your hero's state of mind. Make it clear from his actions. Nor is it necessary to portray many main characters. Let two people be the center of gravity in your story: he and she.
The Bible NEVER flatters its heroes. It tells us the truth about each one of them in order that against the background of human breakdown and failure we may magnify the grace of God and recognize that it is the delight of the Spirit of God to work upon the platform of human impossibilities.
People forget that it is the eye which makes the horizon, and the rounding mind's eye which makes this or that man a type or representative of humanity with the name of hero or saint.
I could not become anything; neither good nor bad; neither a scoundrel nor an honest man; neither a hero nor an insect. And now I am eking out my days in my corner, taunting myself with the bitter and entirely useless consolation that an intelligent man cannot seriously become anything, that only a fool can become something.