Maybe there is another way to look at that voice.

Suppose that you are going to a neighborhood party, and one of the neighbors is loud and difficult. Sort of like that voice. You could try to avoid that person or try to make them stop or change.

Or you could just accept that they are there.

Accepting that they are there does not mean that you approve of them or like them, but it means not railing against them. It means doing what you can to enjoy the party anyways.

We know why that voice is there, we know why all of the self-critical voices are there. They are there because of trauma and depression. Maybe you could say "Oh, it's you again, don't you ever get tired of saying the same thing over and over?" Something like that, kind of irreverent. Accepting that they are there--not believing them!, just acknowledging and accepting that they are there--and doing what you can to make your life what you want it to be in spite of them being there.

I don't want to sound like this is automatically the answer or simple or that it wouldn't be challenging. I do want to give you another perspective to consider.