The Dryad Chronicles: Book One: The Death of a Sacred Tree

After ten years, Charlene Baxter returns to her hometown of Eden, Kentucky. Charlene had left the little coal town as soon as she turned eighteen and only returned to visit her mother and brother. Her younger brother Tommy tells her about a girl named Serafina he plans to marry.
However, the day after Tommy comes from Serafina's, he commits suicide in front of Charlene. Charlene struggles to come to terms with Tommy's suicide while trying to be supportive of her mother. While searching Tommy's room, Charlene runs across a drawing of the mysterious woman Serafina.
Becoming convinced that Serafina had something to do with her brother's death, Charlene begins investigating. Charlene stakes out the abandoned apartment complex with a giant oak tree growing in the courtyard where Serafina lives. She eventually uncovers secrets that will shatter her views on the world and her brother.