I have confessed this to God plenty of times. Is that enough, or do I actually need to say it out loud to another person?

“When I kept silence, my bones waxed old through my roaring all the day long. For day and night thy hand was heavy upon me: my moisture is turned into the drought of summer. Selah. I acknowledged my sin unto thee, and mine iniquity have I not hid. I said, I will confess my transgressions unto the LORD; and thou forgavest the iniquity of my sin. Selah.”

David describes the physical toll of keeping something hidden: bones wasting, strength drying up, a low-grade groaning that ran all day long. Then he says he acknowledged it, and the language changes immediately. Ancient Israel understood confession as something spoken rather than merely thought, and this psalm was sung publicly by people who had all done their share of hiding.

“Confess your faults one to another, and pray one for another, that ye may be healed. The effectual fervent prayer of a righteous man availeth much.”

James writes to congregations in the middle of ordinary trouble, and he pairs confession with praying for one another and with healing. Confessing to another person is not a second requirement stacked on top of God's forgiveness, which is already complete. It is how a thing stops being secret, and secrecy is usually where shame does its most effective work.