Guard of Liberty by Tracie Delaney

Some mistakes are unforgivable—especially hers.

A moment of weakness ruins everything that Liberty Sullivan holds dear. The worst part of it? She has no one to blame but herself. With her marriage in tatters, she returns to her hometown in rural Scotland with her daughter.
Royal Marine veteran, Noah “Sully” Sullivan might have a failed marriage behind him, but damn it, he won’t fail at being a father, too. His ex-wife can try to keep him at a distance, but she’ll have a hell of a fight on her hands.
When a freak accident throws the former couple together again, Sully and Liberty are forced to face up to their shared history and the mistakes they both made.
But with danger lurking in the shadows, and the past haunting the present, does everyone deserve a second chance at love?