The genre is hot – the unreliable protagonist psychological thriller. Think “Gone Girl,” “The Girl on the Train,” “The Woman in the Window.” And now on the best-seller list, “An Anonymous Girl.” Typically, this genre follows a smart and sensitive young woman who soon finds herself in danger, a sympathetic but troubled soul who unwittingly endangers others as she tries to sort out what’s real and what’s the product of her admitted neurotic fantasies. The reader is drawn into the complications, not sure what to believe, as new information, from other points of view, alters what’s known about identities and relationships. Friends grow suspect, loved ones disappoint. When done well, this kind of twisty tale drives to a fast-paced violent conclusion, as satisfying as it is inevitable. Wendy Walker’s new thriller, “The Night Before,” almost makes it. Laura Heart, born Laura Lochner, has left a good job in New York to live with her sister Rosie in a small city in Connecticut, but not before a