The Way Back. Hired Hearts Series, #1

Keon Kitson has lost his five-year-old son in a car accident, the same way he lost his parents when he was a kid. His fiancée left him before he woke from a coma. Keon can't see past the pain in his heart and the darkness surrounding him. He wants to give up on life, but his best friend keeps pushing him to go on--as if it could ever get better. Shakita Chambers has just landed a dream job working with a man she's admired for years.
She would love to learn all she can from Keon, a world famous author. Except Keon is broken. He's determined to drink himself into the grave, starve himself there, or tick her off so bad she kills him herself. Despite Keon's ugly attitude, Shakita is attracted to him. One minute they're arguing, the next they can't keep their hands off each other. Shakita knows she's playing a dangerous game. Keon still loves his ex, and his ex won't let him forget it.
Shakita's worried about her heart, and so is every other interfering busybody in her life.