Being a son (small "s") of God through Christ is all the self-esteem I need. Jn. 1:12, Rom. 8:14. What an undeserved honor it is to be a joint-heir with Christ!
As for psychology, it is garbage. The best one can hope for through psychology is to exchange one neurosis or mental crutch for another which society deems less harmful or disruptive. Psychology is a manipulation of one's thoughts and attention in the attempt to focus on positive outcomes. The problem is that when one's entire mind is sinful and "conformed to this world" (Rom 12:2), trying to manipulate the thinking patterns merely leaves a person in a sinful, errant state of being.
The medical industry doesn't even bother with psychology anymore. Psychiatry (hard-core neuroleptic and antidepressant drugs) is the name of the game now. They just want to drug people into a numbed-out state where they are less likely to hurt themselves or others. What a sorry substitute for regeneration!