Airhead: Being Nikki (Airhead Trilogy)

Plot

Emerson Watts is on the run: from school, from her family and from herself. She's reeling from the shock that Nikki, the girl whose body her brain was forced to inhabit, is still alive. And she's furious. Manipulative Brandon plans to use Em to discover a secret that will ensure his succes, whilst Christopher is out for revenge, fuelled by his jealousy. With everyone around her playing a dangerous game, maybe Em should just keep on running.