Tarzan

 In the Disney movie, Tarzan and Jane end up together after Jane realizes that she'd rather live in the jungle with her true love. However, in the original book, she just stays with Clayton because she feels she has no choice in the matter. Tarzan gets the chance to save her and take her with him, but he thinks that she's happy with Clayton, and so he leave, with him and Jane being miserable. It's not until the next story that Tarzan and Jane actually get married.

Tarzan of the Apes