Mistress

Mistress by James Patterson

From the Goodreads website:

"Ben isn't like most people. Unable to control his racing thoughts, he's a man consumed by his obsessions: movies, motorcycles, presidential trivia-and Diana Hotchkiss, a beautiful woman Ben knows he can never have. When Diana is found dead outside her apartment, Ben's infatuation drives him on a hunt to find out what happened to the love of his life. Ben soon discovers that the woman he pined for was hiding a shocking double life. And now someone is out to stop Ben from uncovering the truth about Diana's illicit affairs. In his most heart-pumping thriller yet, James Patterson plunges us into the depths of a mind tortured by paranoia and obsession, on an action-packed chase through a world of danger and deceit."

This was great for airplane reading.  It was easy to keep up with the plot, no weird twists that I couldn't follow.  Just a simple, entertaining book.