The backup plan : a novel / Jill Shalvis.

When Alice receives a call about an unexpected windfall, she's stunned to learn the gift is a falling-apart-at-the-seams old Wild West B&B she once considered home--and she's inherited it along with two strangers. Except they weren't always strangers. Once upon a time, they were friends. One is her ex-BFF Lauren. The other is Knox, the only guy to ever break her heart, all while never even knowing she existed. It turns out their lives are unknowingly entangled because they once separately helped the same woman without expecting anything in return. Years later, Alice, Lauren, and Knox are broken in their own way, with their own history--and secrets-- causing them to start out on the wrong foot with each other. But according to the will, they must renovate and be partners in the inn for one year or else lose their inheritance. Stuck together, they make a list of rules to keep the peace--rules that end up doing the opposite, but by some miracle they find what they didn't even know they were looking for--acceptance, true friendship, and in a case (or two!), true love.