In Mistletoe by Tammy L. Bailey

At twenty-five, Grace Evans is steadily picking up the pieces of everyone else’s life. So, when her younger sister decides to turn into a runaway bride just four weeks before the wedding, Grace, drops everything to chase after her and bring her back home. Only, when the trail leads to Mistletoe, Washington, she finds herself at the mercy of the town’s most handsome and emotionally unavailable bachelor.

Ex-Army officer, Ayden McCabe, has three creeds in life: never make the first move, never fall in love, and never take anyone to Mistletoe’s Christmas Dance. Wanting nothing more than to keep his matchmaking sister from meddling in his personal life, he agrees to help Grace if she agrees to play his girlfriend. Too brunette and meek for his taste, Ayden believes Grace can’t tempt him enough to break any of his creeds. He could not be more wrong.