White Christmas With My Enemy by K. M. Ryan

Candace’s sister is getting married to the man of her dreams in the perfect place. What isn’t so perfect is that the groom’s brother is Candace’s enemy… and that a snowstorm strands them in the small town of Wintervale, Montana.
The only problem is she’s holding an eleven-year grudge over something he doesn’t even remember.
Brent doesn’t understand why Candace despises him so much, but he feeds into it, irritating her every chance he gets. But after a skiing accident, Brent wants to be the person to help.
Can Brent break through Candace’s cold exterior, or will she continue to ice him out?

Series Blurb:
Find romance in the 12 Days of Christmas from 12 of your favorite romance authors. From enemies to lovers, MCs, friend’s sister, age gap, billionaires, grumpy/sunshine, and more, look no further to find your perfect Christmas boyfriend.