hard-heartedness

If the servants had not already remarked on her hard-heartedness, she would have cried herself ill.

Take notice of the doleful effects of hard-heartedness in the world.

This unkindness is oftentimes unintentional, and due more to thoughtlessness than to deliberate hard-heartedness.

The civilian stared at the coolness of the soldier, which seemed to him much like hard-heartedness.

It is not hard-heartedness or bitterness that makes me think of your future now—and makes me wish to spare you disappointment.