If You're Lucky by Yvonne Prinz
"When seventeen-year-old Georgia’s brother drowns while surfing halfway around the world in Australia, she refuses to believe that Lucky’s death was just bad luck. Lucky was smart. He wouldn’t have surfed in waters more dangerous than he could handle. Then a stranger named Fin arrives in False Bay, claiming to have been Lucky’s best friend. Soon Fin is working for Lucky’s father, charming Lucky’s mother, dating Lucky’s girlfriend. Georgia begins to wonder: Did Fin murder her brother in order to take over his whole life?
Determined to clear the fog from her mind in order to uncover the truth about Lucky’s death, Georgia secretly stops taking the medication that keeps away the voices in her head. She is certain she’s getting closer and closer to the truth about Fin, but as she does, her mental state becomes more and more precarious, and no one seems to trust what she’s saying.
As the chilling narrative unfolds, the reader must decide whether Georgia’s descent into madness is causing her to see things that don’t exist--or to see the deadly truth."- summary from Amazon
This was a really interesting, suspenseful book and the final sentence of the summary is very true- I began to wonder if this was all in Georgia's head or if there was something wrong with Fin. I was definitely leaning toward the latter because it seemed like the right course for the novel but Prinz does a pretty good job of providing that counterbalance.
FTC: Received hardcover from publisher. Link above is an Amazon Associate link; any profit goes toward funding contests.