This article examines Freud's theory of depression based on his paper “Mourning and Melancholia” from the structural determinist paradigm. The reality of depression lies in the underlying structure of the mind in which Freud's libidinal drives and topographical structure of mind bring forth conflicts in relation to an object. Freud delves into the fundamental causes of depression and points out that loss of object, regression of libido into the ego, and ambivalence cause hidden conflicts, which manifest themselves as depressive symptoms and feelings. William Styron's Darkness Visible is used to illustrate its relevance to the structural determinist aspects of Freud's psychoanalytic theory of depression.