The purpose of this paper is to better understand the psychodinamic process of love and hate, their coexistence within one relationship and transformation of one affect into another. Through the work of Freud, M. Klein, Kernberg and many others, the origins of love and hate from infancy have been explored, as well as the way how they develop through the life cycle. Mature love relationships are considered to reflect earlier feelings, those experienced first in the relationship of the child with its mother and, later, with the Oedipal parent. Therefore, successful achievement of a mature relationship depends on the person having been able to negotiate prior conflicts successfully. In the case of an unresolved problem, his or her capacity to fall in love will be limited. Hate is not necessarily negative. Its developmental necessity suggests that hate may also subserve adaptation and personality organizations. This is also argued of narcissism, which, if not excessive (healthy narcissism) contributes to a better sense of self and the preservation of one's own identity. However, excessive narcissism can be considered both as too much of self love as well as an incordinated and excessive hate disorder, that unables forming a deep and meaningful love relationships with others. Due to the fact that both love and hate are developmental milestones, and such passionate feelings directed toward one person, it is easy to understand that great love can turn into great hate rather than indifference. Finally, we have also explored how the revange operates and the importance of forgiveness, which allows love to dominate hate in these ambivalent love relationships.