The Ill-Made Mute by Cecilia Dart-Thornton.

In a world where creatures of legend haunt the lands of men, and to be caught outside after dark means almost certain death, the inhabitants of Isse Tower are amazed when a mute, starving foundling is discovered outside their gates. With no recollection of her name or past, the girl soon realizes that her only hope of happiness lies in distant Caermalor, where a wise woman might be able to restore her memories. To get there, Imrhien must survive a wilderness of endless danger. Lost and pursued by unhuman wights, Imrhien is saved by Thorn, a mysterious, handsome ranger who becomes her protector-and the object of her hopeless love. But unknown to them, a dark force summons the Unseelie, and malignant hordes amass in the night.