And I certainly should be if I didn't know that your people are human beings." She looked guilty as well as angry now.

She felt she had gone just the one short step too far in her aristocratic assumptions.
He went on in the tone of one who confidently expects that there will be no more nonsense: "When you married me you had some sort of idea how we'd live." "I assumed you had thought out those things or you'd not have married me," cried she hotly.

In spite of her warnings to herself she couldn't keep cool.

His manner, his words were so inflammatory that she could not hold herself from jumping into the mud to do battle with him.

She abandoned her one advantage--high ground; she descended to his level.
"You knew the sort of woman I was," she pursued.