Natural Selection by Elin Hilderbrand

When her boyfriend bails at the last minute, a New York woman embarks on their couples’ cruise alone to find that maybe the person she was supposed to fall in love with was herself.

After a string of bad dates and no prospects, Sophia Othonos has finally hit the jackpot: an actual nice guy. When he suggests a romantic getaway, she’s sure they’re about to take the next step toward their future. A rustic cruise to the Galápagos Islands isn’t exactly her idea of a vacation, but Sophia is ready for anything…until her boyfriend has to cancel.
Now she’s all alone on a trip that was meant for two. Sophia finds herself at a crossroads about who she is, what she wants, and whether her relationship is really everything she thought. But if she’s going to suffer an identity crisis, at least she gets to do it amid the unexpected majesty of nature.
Eight days of wild, unobstructed beauty are enough to make anyone reevaluate their life. These islands are all about adapting to your surroundings—and change just might be what Sophia needs most of all.