The Boyfriend by Freida McFadden

Sydney Shaw is single, unlucky in love, and exhausted by the dating scene. When she meets Tom, charming, attentive, successful, and seemingly perfect, it feels like she’s finally caught a break. Their relationship moves quickly, but not so fast that it feels unrealistic. In fact, that’s part of what makes this book work: everything feelsplausible. But then women in the city start disappearing. And suddenly, the question isn’t whether Sydney has found the right guy, it’s whether she’s made a catastrophic mistake.