How and what does Euripides' Medea teach us?

I
believe the play should teach us to recognize the reality that some women can be so filled with
resentment and hatred for a man who has abandoned or otherwise mistreated them that they will
turn their anger on the children he fathered. If the children are boys, the mother can merely
reject them or go so far as to abuse them mentally or physically, or both. Some mothers may
disguise verbal or physical abuse as discipline or instruction. Young children are easy victims
because they trust their mothers and want their mothers' affection. They are likely to believe
that they are responsible for the rejection or abuse they receive; they can develop lifelong
guilt or inferiority complexes as a result. If the children are girls, the mother may condition
them in various subtle or overt ways to feel a hatred of men which could make the girls' lives
as unhappy as their mother's. Miss Havisham in Charles Dickens' novel Great
Expectations is an example of how a mother-figure can teach a girl to share her
hatred and desire for revenge against the male race. Another good example is the mother in D. H.
Lawrence's short story "The Rocking-Horse Winner."

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. 

A really harrowing story of abuse of a child by a mother is the memoir A
Child Called "It." (See the reference link to the e-Notes summary of this
book below.) Extreme hatred can lead to insanity, and insanity can lead to anything, including
murder. is not just a story about one woman but an extreme example of a
fairly common type of human behavior, much of it hidden behind closed
doors.