Muise, AmyUppot, Akshita Ajay2025-11-112025-11-112025-07-302025-11-11https://hdl.handle.net/10315/43298Sexual desire declines and is challenging to maintain after the initial “honeymoon phase” of a relationship. One promising factor for explaining the trajectory of desire is self-expansion—broadening one’s sense of self through novel and exciting experiences with a partner. The current study is the first to longitudinally track desire and self-expansion in early dating couples (N = 170 couples, relationship length = 3 - 15 months) to test whether higher self-expansion buffers against the typical declines in desire. Over the 18 months, desire and self-expansion declined then levelled off showing both linear and curvilinear effects. People who were generally higher in self-expansion, and at times when they felt higher self-expansion than usual, reported higher sexual desire, but this did not protect against declines in desire over time. For women specifically, partner’s self-expansion was associated with a boost in desire but also steeper declines. Implications for self-expansion theory and sexual desire maintenance are discussed.Author owns copyright, except where explicitly noted. Please contact the author directly with licensing requests.Social psychologyElectronic Thesis or Dissertation2025-11-11Romantic relationshipsEarly datingSexualitySexual desireSelf-expansion