Sugar Queen by Sarah Addison Allen

Wonderful book! Josey is a very young old lady. Her mother married the richest man in town, had Josey very late in life and now keeps her around so she won't be alone. Then Della Lee shows in Josey's closet and decides it is nicer to live there than with the mean boyfriend. She begins pushing Josey to rebellion and soon Josey finds a new best friend and a boyfriend. A book with just the right blending of mystery, romance and magic.