Focusing on attractive alternative partners when one is already in an established relationship can lead to several negative outcomes, including infidelity and relationship dissolution. The extent to which individuals attend to and remember such alternatives, however, may be affected by various factors within the relationship, including love for the partner, commitment to the relationship, and self-expansion in the relationship. This research examined the role of such relationship factors in predicting cognitive processes associated with attractive alternatives. Specifically, two studies tested hypotheses derived from the self-expansion model of close relationships (e.g, Aron et al., 2000) that predict key factors associated with attention to, and memory for, attractive alternative partners. Study 1 examined the relative influence of romantic love, commitment, and relational self-expansion in reducing attention to attractive alternatives. Study 2 examined need for self-expansion (in one's life in general) and how this may affect attention to, and memory for, alternatives, as well as the type of alternatives one may find appealing. Love for the partner predicted reduced visual attention to photos of attractive alternatives. Love, commitment, and relational self-expansion were associated with reported attention to alternatives. Further, need for self-expansion predicted memory for (but not attention to) alternatives that differed from the partner in terms of self-expansion promoting attributes, which could therefore supplement one's level of self-expansion. Implications regarding the application of the self-expansion model to the study of infidelity are discussed, as well as potential directions for future research.