Antonyms for the phrase "showing tenderness" could include harsh, cold, unfeeling, indifferent, rough, cruel, callous, insensitive, unfriendly, and uncaring. These antonyms describe behaviors that are opposite in nature to displaying tenderness, which involves being caring, gentle, empathetic, kind, loving, and compassionate towards others. While "showing tenderness" implies a certain level of emotional intelligence and sensitivity, the antonyms showcase a lack of understanding, empathy, and emotional intelligence towards others who may be going through a difficult time. Therefore, it's important to be mindful of our actions and words and consider how they may affect others.