The Nearness of You by Amanda Eyre Ward

Brilliant heart surgeon Suzette Kendall is stunned when Hyland, her husband of fifteen years, admits his yearning for a child. From the beginning they'd decided that having children was not an option, as Suzette feared passing along the genes that landed her mother in a mental institution. But Hyland proposes a different idea: a baby via surrogate. Suzette agrees, and what follows is a whirlwind of candidate selection, hospital visits, and Suzette's doubts over whether she's made the right decision. A young woman named Dorothy Muscarello is chosen as the one who will help make this family complete. For Dorrie, surrogacy (and the money that comes with it) are her opportunity to leave behind a troubled past and create a future for herself—one full of possibility. But this situation also forces all three of them—Dorrie, Suzette, and Hyland—to face a devastating uncertainty that will reverberate in the years to come.