Use 'unfeeling' to describe someone who does not respond emotionally where it's normally expected. His unfeeling response to the tragedy shocked everyone.
Pro Tip 2/3
Lacks Compassion
'Unfeeling' implies a lack of empathy and understanding towards others' emotions. The judge's unfeeling remarks made the plaintiff cry.
Pro Tip 3/3
Criticism Implication
'Unfeeling' often carries a negative judgment, criticizing a person's lack of sensitivity or kindness. Calling her an unfeeling boss, the employees expressed their dissatisfaction.