Pawns of Fate by Trixie Woodlawn

Rose Robson has always been an outsider. Used as merely a pawn in her uncle’s political games, she was never taught the full extent of her magic abilities. Rose longs for a family that cherishes her, but fears that dream will forever be out of reach. Now faced with a marriage arranged by her uncle, Rose decides to accept her fate and make the best of the situation.
Nicholas Sharp has a duty as the oldest son to use whatever connections he can to strengthen his family’s position. Being the family’s least talented lightning mage has made him a practical man, so his father’s plans to strengthen ties with their western neighbors, the Robsons, through Nicholas’s marriage don’t surprise him.
Yet, at a celebration for Luanna—the woman Nicholas is to wed—he is unexpectedly introduced to her cousin, the kind, elegant Rose. Impressed with Rose’s grace and charm, Nicholas takes a chance and asks to marry her instead.
But there’s far more at play than just a union between noble houses in a land teeming with monsters and magic. The rise of sinister powers risks destroying more than just alliances; it threatens the balance of their world. Will Rose and Nicholas overcome the rising darkness, or will they forever be doomed as pawns of fate?