There are two ways to change 1. loading a save before the nameless choice and 2. Restarting the whole game
Actually, neither of these things will work to change your statement to the Nameless - it is locked once made. Starting over or reloading will not allow you to change it.
There may be a way to delete the game's data from your account. Otherwise, I'd just be careful in the future that you pick the option you mean when concerning the Nameless.