Stuck in the Cabin by Sarah J. Stone

Brought together by a boss neither could stand, Neil and Stephanie fall in love while learning to work together against him. Sent on a trip to a remote cabin over the Christmas holidays, they find the one thing each of them so desperately needed: each other.
As events unfold around them, the secret Neil carries could spell disaster as his past leads him home to Ireland and into a world that Stephanie could never have imagined.