To Rise Again at a Decent Hour by Joshua Ferris
Paul O'Rourke is a man made of contradictions: he loves the world, but doesn't know how to live in it. He's a Luddite addicted to his iPhone, a dentist with a nicotine habit, a rabid Red Sox fan devastated by their victories, and an atheist not quite willing to let go of God. Then someone begins to impersonate Paul online, and he watches in horror as a website, a Facebook page, and a Twitter account are created in his name. What begins as an outrageous violation of his privacy soon becomes something more soul-frightening: the possibility that the online "Paul" might be a better version of the real thing. As Paul's quest to learn why his identity has been stolen deepens, he is forced to confront his troubled past and his uncertain future in a life disturbingly split between the real and the virtual.