What would a black person "talking white" mean? Do you mean the manner in which a black person & role model, such as Oprah Winfrey, speaks?

If so, I think Oprah comes across as very intelligent and well-spoken.

As for this girl bothering you, guess what? There will like be other people in your life will probably bother you, too. You need to move on with your life and not worry about others.