Secrets in the Shadows by Virginia Andrews
Everyone says her mother was mad. Is she doomed to repeat the past? Up in the attic, that's where Alice's mother used to escape to - and it's where, so Alice has been told, she plotted the murder of her own stepfather. Now, years later, with her mother locked away for life, the attic is where Alice finds comfort in her solitude, writing poetry and painting pictures. When Alice finally finds the courage to come out of her shell, exchanging her dowdy looks for flattering clothes and make-up, her life is completely transformed. She even attends her high school prom with a cute, popular boy. But it's a night that suddenly turns tragic - sending her new-found happiness crashing down around her, and hurtling Alice into a shattering new life, one that leads her to a shocking reunion with the shadows she had fled.