The Fury and the Power by John Farris
Series: The Fury, Book 3.
Approx. 112,390 words.
Published on November 27, 2012 by
Eden Waring has known fear in her life. She is an Avatar, a talented young psychic with the ability to produce at will her doppelganger - her mirror image, who calls herself "Gwen" and possesses remarkable powers beyond even Eden's gifts. Gwen can be invisible to mortal eyes, if she chooses to be, and can even travel back and forth in time.