One of the central themes of One True Loves, in keeping with both the romance genre and the title, is the idea of soulmates and everlasting love. These concepts are explored in the novel through a love triangle, a popular romance trope. This context is established in the Prologue, where an engaged Emma suddenly receives a call from her missing husband, who survived a helicopter crash. As the details of the situation are gradually revealed, it becomes evident that these are not frivolous circumstances. Emma loves both husband Jesse and fiancé Sam, and must grapple with the former’s reemergence.

The first part of the novel explores Emma’s relationships with both men. Jesse is set up as her soulmate from the start—even as their high school romance unfolds, the reader already knows that Emma will eventually marry him. Emma falls for Jesse the moment she sets eyes on him, and her love is eventually requited: After their first conversation, Jesse is equally smitten with Emma. The night of this conversation ends in a kiss, which sparks a summer romance that matures into a relationship. Emma and Jesse encourage each other to break free of familial and societal expectations, and to follow their dreams.