Electra's hate against her mother—although intensified by the murder of Agamemnon—contains also the rivalry of the daughter with the mother, which focuses on not having had her sexual desires gratified by the father. These early disturbances of the girl's relation to her mother are an important factor in the development of her Oedipus complex.
Klein argues that Electra's hostility toward Clytemnestra is not merely reactive but expresses the daughter's unfulfilled sexual desire for the father alongside early pre-Oedipal disturbances, thereby grounding the Electra complex within her broader theory of the female Oedipus complex.
, Envy and Gratitude and Other Works 1946-1963, 1957thesis