You do not have to publicly admit or apologize for voting incorrectly in the last election. People make mistakes. There are three things you must do now.
1. Accept the forgiveness of the universe
2. Forgive yourself
3. Make up for your mistake at the ballot box
Several groups have formed for Republicans who regret their 2016 vote and millions are joining them. Namely, The Lincoln Project.
You are not alone. Trump does not represent Republican values, principles and ideals. Vote him out.