What is the name of this young adult fic book I read approx 15 yrs ago?

It was I believe called Avi, or what ever the main girl's name was or the ape, chimp or gorilla she became. She was in a coma after a wreck and she woke in a bed disoriented and she thought she was paralyzed. There was a mirror above her so she could see around the room but she could not see herself. As she recovered she began having dreams of the forest. In the end she discovered that to save her life her father did surgery to place her brain or something into the chimp/gorilla in his care. She was acting out as a hormonal ready to breed ape. She was released by her father into the forest she had been dreaming of as the ape side of her needed.