Rush by Elle Thorne

The first mate of the Javelin’s got it bad for a nasty-tempered, smart ass woman from Earth. That she’s promised to handfast another man sits on his conscience. He shouldn’t have kissed her. He shouldn’t have cared. These things don’t sit on his conscience as much as the secret he’s been keeping from the ones who trust him.
Katrina agreed to be a mail order bride to the wrong man. Okay, any man would have been the wrong man because she had eyes for one alien, and one alone. But she can’t take the luxury to develop feelings for him. She’s on a mission. And if her mission fails, her family’s life is at stake.
Hop on board the Javelin for a ride into another solar system and a journey into the lengths one goes for love.