How does David's mother become a victim of her husband?

David's mother, Clara, marries Mr. Murdstone, who appears handsome and charming at first but proves to be sadistic and hard-hearted. Clara becomes his "victim" in that he is able to dominate her through the force of his will and insists that she learn "firmness" in her dealings with David. In fact, Murdstone is an example of "toxic masculinity"—he believes that, as a man, his views cannot be challenged; emotionally manipulates others (Clara) to get his way; and is not afraid to use physical violence to enforce his will. Indeed, it seems the object of his desire for "firmness" is to punish David and that he derives a kind of repressed pleasure from corporal punishment. Murdstone effectively destroys Clara emotionally by perverting the one thing that gave her life meaning, which was her love for David.

David's mother Clara is a sweet and gentle creature, far too fragile for this harsh, unforgiving world. Eight years after David's father dies, his mother remarries. Unfortunately for her, and for her son, she makes a really bad choice. When David comes home after visiting Peggotty's family, he discovers that he has a new stepfather, Mr. Murdstone. Murdstone is a thoroughly nasty piece of work. He is a cold, sadistic bully who proceeds to treat his blended family like dirt. As well as beating poor David at the drop of a hat, Murdstone and his equally disgusting brood take full advantage of Clara's trusting nature, subjecting her to a campaign of psychological abuse and intimidation. Before long, the Murdstones have taken over control of the household, and Clara effectively becomes a stranger in her own home.