Authentic characters resonate throughout this engrossing novel from Duffy (The Salt House) as a woman tries to understand why her husband, a soldier with PTSD, has left her. Quinn Ellis's husband, John, was deployed twice in their five years of marriage; after the last tour, he came back to their home in Massachusetts but soon after disappeared. Quinn's work as a nanny is the only thing keeping her anchored while she tries to find John and waits for him to get in touch with her. After receiving a notice that her lease won't be renewed, Quinn accepts an offer from John's former sergeant, Bent Winters, a local cop in Paradise, Mass.: she can stay on the first floor of the triple-decker he lives in with his sisters, Lucy and Desiree, and his teen daughter, Libby. Alternating points of view from Libby and Quinn provide the contrasting perspectives of a teenage girl on the brink of adulthood and a wife coping with the sorrow and guilt of her fractured marriage. Over time, Quinn and Libby come to see each other as family, healing their mutual loneliness. A healthy dose of humor balances the sadness of Quinn's story. Intensely real and deeply emotional, Duffy's rich novel is worth savoring from the very first page. Agent: Danielle Burby, Nelson Literary. (June)