The Breakaway By Jennifer Weiner

From #1 New York Times bestselling author Jennifer Weiner comes a warmhearted and empowering new novel about love, family, friendship, secrets, and a life-changing journey.
Thirty-three-year-old Abby Stern has made it to a happy place. True, she still has gig jobs instead of a career, and the apartment where she's lived since college still looks like she's just moved in. But she's got good friends, her bike, and her bicycling club in Philadelphia. She's at peace with her plus-size body—at least, most of the time—and she's on track to marry Mark Medoff, her childhood summer sweetheart, a man she met at the weight-loss camp that her perpetually dieting mother forced her to attend. Fifteen years after her final summer at Camp Golden Hills, when Abby reconnects with a half-his-size Mark, it feels like the happy ending she's always wanted.
Yet Abby can't escape the feeling that some­thing isn't right...or the memories of one thrilling...