I'm simply saying, first of all, that Marxism isn't a "theory of everything." It's not a theory designed to answer such questions as "why humans do the sometimes strange things they do" (Zizek) and "why Flaubert preferred literature to everything else, lived like an anchorite, etc." (Sartre). Nor can psychoanalysis explain the causes of such phenomena, except that it may allow us to believe as if the questions were answered (just as religion may). Like Stephen Jay Gould, I'm opposed to an adaptationist school of thought enamored with the idea of pervasive utility. Give contingency a chance.
I agree with Carrol on a lot of things, despite our different backgrounds, and despite our agreements on many things political, we just don't like the same authors (most of the authors Carrol likes -- Milton, Pope, Henry James, Pound, etc. -- are, alas, not my favorites). One may find this fact "strange" and can endeavor to provide a "psychological," even "psychosocial," explanation of these agreements and disagreements, but there is no point in doing so.
Secondly, a "psychological explanation" of X occludes a historical explanation of X. What is known as "homophobia," for instance, isn't a part of "eternal human psychology"; it's a historical phenomenon, for instance, unknown in premodern Japan. Trying to explain "homophobia" with references to the "Unconscious," etc. falsely eternalizes it, as if it were part of unchanging "human nature."