How does Medea inform contemporary psychology?

The ancient Greek tragedy Medea by Euripides would not be of much interest to modern readers were it not for the fact that it dramatizes a conflict which has existed throughout history and is readily observable today, although abandoned wives are less likely to murder their children than they are to hate and reject them. Just as Sigmund Freud named the Oedipus Complex after the play Oedipus Rex by Sophocles, because Freud believed that every man has a unconscious wish to kill his father and marry his mother, so the play Medea has given its name to what psychiatrists call the Medea Complex. This psychological complex is defined in Segen’s Medical Dictionary as follows:
MEDEA COMPLEX Murderous hatred by a mother for her child(ren), driven by the desire for revenge on her husband; it is a reference to Medea of Greek mythology, who kills her children.
It is easy enough to understand how a change from love to hatred could come about. We can imagine the feelings of a woman who has been abandoned by her husband. She is left to raise his children by herself. They are not only a burden to her financially, but they make it extremely difficult for her to marry again. Few men are willing to take on an entire family and raise another man’s children. If the children happen to be boys, as they were in Euripides' tragedy, they can remind their mother of the unfaithful husband she has come to hate, and the hatred she feels for him may be transferred to them.
Heav'n has no Rage, like Love to Hatred turn'd,
Nor Hell a Fury, like a Woman scorn'd.
William Congreve, 1697
A perfect modern example of the Medea Complex to be found in modern literature is D. H. Lawrence’s story “The Rocking Horse Winner.” The story opens with the following brilliant description of a mother’s thoughts and feelings:
There was a woman who was beautiful, who started with all the advantages, yet she had no luck. She married for love, and the love turned to dust. She had bonny children, yet she felt they had been thrust upon her, and she could not love them. They looked at her coldly, as if they were finding fault with her. And hurriedly she felt she must cover up some fault in herself. Yet what it was that she must cover up she never knew. Nevertheless, when her children were present, she always felt the centre of her heart go hard. This troubled her, and in her manner she was all the more gentle and anxious for her children, as if she loved them very much. Only she herself knew that at the centre of her heart was a hard little place that could not feel love, no, not for anybody. Everybody else said of her: “She is such a good mother. She adores her children.” Only she herself, and her children themselves, knew it was not so. They read it in each other’s eyes.
No matter how hard Paul tries to win back his mother’s love, the boy is unable to succeed. He miraculously and magically accumulates a fortune in order to buy her love and ends up killing himself in the attempt. The story closes with the following pathetic exchange between Paul and his mother.
“I never told you, mother, that if I can ride my horse, and get there, then I’m absolutely sure—oh, absolutely! Mother, did I ever tell you? I am lucky!
“No, you never did,” said the mother.
But the boy died in the night.