Love by a Landslide (Stranded in Leavenworth #1) by KL Parsons:
 
Lucy O’Malley is done being a doormat. After getting dumped and booted from her apartment on her thirtieth birthday, she finds herself on the road to reinvention—or rather, on Interstate 90 headed east toward Leavenworth, Washington, for a little beer, bratwurst, and backpacking. Who cares if the Bavarian-themed “romantic getaway” was originally planned for a couple? Unfortunately, her guide does.

Jonathan Miller owns Off the Beaten Adventures, a successful outdoor guiding company in Leavenworth. Ever since the unthinkable happened on a rafting trip four years ago, Jonathan has erred on the side of caution. He plans meticulously and avoids risk whenever possible. So, when a sexy little brunette shows up and throws a wrench in his carefully laid plans he is convinced the three-day excursion will end in disaster.

The initial attraction is mutual, but Lucy and Jonathan find themselves on rocky terrain, and the last thing either wants is to complicate matters with a fling. But after a freak landslide decimates their only serviceable trail home, sizzling chemistry is the least of their problems. Together, they must cut through the raw wilderness and return safely to civilization with their bodies—and hearts—intact.