Evidence is presented that Freud developed three very different theories on love. These theories were not integrated into a coherent theory. In subsequent developments each theory had its own history. The paper discusses the history of the controversy on the genital character, the relation between love and gender identity, between love and narcissism, the hierarchical structure of the capacity to love, and the relation between love and object loss. The impact of some concepts such as symbiosis and the rapprochement subphase on the understanding of conflicts in loving is raised. While at present differences in emphasis make it difficult to build a coherent psychoanalytic theory of love, it is productive to bring divergent views in touch with each other. A unified theory of love based on psychoanalytic observations is suggested.