"I don't need some Catholic priest to tell God my sins for me."
That's not what happens in Confession. After all, it's not like you're telling God anything He doesn't already know.
The priest is there to advise you as you accuse yourself of your sins before God, and to help you to a good examination of conscience.
Then, in reliance on the word of Our Lord as set forth in Holy Scripture, he grants Absolution and assigns penance.
It's a wonderful thing. I can literally feel the weight of my sins lifted from my shoulders when the priest pronounces those beautiful words: ego te absolvo...I absolve you...
Our Lord is present in a special way in the Eucharist. It is my belief that He is also present in a special way in the confessional.
I trust in Jesus Christ when I confess my sins, not a mere mortal.
Jesus Christ, the ONLY mediator between God and man.