The water child / Mathew West.

"What the sea takes for its own can never return... Portugal, 1750s. Cecilia Lamb knew being a sea captain's wife would mean a life of waiting and watching the horizon for her husband's ship. But John has been gone longer than any voyage should last. Everyone else has given up hope of his return. But she knows in her bones that he is not lost. Gone, but not lost. Barely able to tear her eyes from the shimmering sea, she feels drawn to the sun-baked shoreline, and amid the bustle of the docks she feels certain that her husband will come back to her. Though along with that feeling is another sense - that something darker is coming. As she sickens, she doesn't know what the next tide will bring - but she begins to fear as well as crave her husband's homecoming. Soon, even on dry land, Cecilia can feel the pull of the ocean at her feet, the movement of the tides within her. Warning, seduction or promise, she cannot tell, but one thing is certain - the sea holds many secrets, and some of them are too powerful to ever be drowned"--Provided by publisher.