Telling secrets to yourself seems like a pointless activity. Why would you confess to yourself something you already know? Your secrets are inside your head, yes, but they exist as nebulous, unorganized ideas.
In the same way that writing a list of pending tasks helps you clear your mind and structure your thoughts, sharing your secrets with a piece of paper or a text file will help you organize those ideas that have never had the chance to leave your mind.
You don’t need to share your secrets with the world. Just make a confession to yourself. The words that come out might surprise you, as if you were hearing someone else’s secret.