If Only I Had Told Her is a companion work to If He Had Been with Me, another young adult romance. If Only I Had Told Her focuses on Autumn’s perspective on losing Finn, but it also traces their relationship further back, returning to the beginning of high school to examine many moments between Finn and Autumn. Throughout the early narrative, Autumn and Finn do not behave as former friends normally would, implying their romantic interest in each other. However, Autumn does not realize that she has romantic feelings for Finn until junior year of high school, at which point she resigns herself to not having him; he is with Sylvie and she remains with her boyfriend, Jamie. During senior year, Finn and Autumn have a class together that brings them into more contact with one another, and their friendship tentatively rekindles.

After graduation, Autumn finds out that Jamie is cheating on her with their mutual friend Sasha. This causes them to break up and leads to Autumn’s depression that summer. Meanwhile, Sylvie is in Europe, so Finn spends more time with Autumn.