The antonyms for the word "commiserating with" would be words that suggest a lack of empathy or understanding. Some potential antonyms might include: criticizing, blaming, berating, scolding, condemning, or disregarding. These words all express a negative judgment toward someone's situation or feelings, rather than offering support or compassion. If you want to express the opposite of "commiserating with," you might use terms like congratulating, celebrating, complimenting, or encouraging, which all express positive emotions and recognition for someone's achievements or good fortune. Ultimately, the choice of antonym will depend on the specific context and tone of the conversation, as well as the relationship between the speaker and the person they are addressing.