Opposite of always
(Book)

Jack and Kate met, bonding until sunrise over their mutual love of Froot Loops and their favorite flicks. Jack falls-- hard. But then Kate dies. Somehow Kate's death sends Jack back to the beginning, the moment they first meet, and Kate's there again. Healthy, happy, and charming as ever. Jack thinks he's losing his mind-- but takes the chance to prevent Kate's death. He learns actions are not without consequences when it turns deadly for someone else close to him. Now Jack has to figure out what he's willing to do to save the people he loves.-- adapted from jacket