Sinbound to the Highlander by Eloise Madigan

Love’s other name is revenge…

Knowing she was adopted, Freya Crushom never thought that she would be the daughter of a Laird until a kind Highlander reveals her true birthright. With her whole life upside down, her heart tears between him and her duty to her new family.
For Evan Saunderson, Laird of Ruthven, an arranged marriage is the only solution to his clan’s threat of war. But his plans change, when he finds his betrothed’s identical twin staring down at him in the woods, bewitching him with her eyes.
The only thing that seems to disrupt their false sense of tranquility is Freya’s sister missing. But that is only a deadly scheme by someone who seems to have forgiven but never forgetten…and Evan is the only person able to unveil it.