“‘I kept my mouth shut. I didn’t answer him.’ A grim and furious silence can be more crushing and wounding than harsh words. Such a silence is motivated by the desire to punish. It is the fruit of bitterness and resentment.” (ODAT, 25 March)
Sometimes the diplomatic thing to do is to remain in the conversation but remain neutral, neither actively supporting the person’s standpoint nor contradicting or opposing it.
One can listen and indicate that one is listening with all of the ordinary verbal fillers of ‘yes’, ‘no’, ‘right’, ‘I get that’, ‘of course’, ‘uh-huh’, ‘gosh!’, ‘I get that’, ‘that’s natural’, and the scores of other options.
Every language has them.
In French: ‘en effet’, ‘quand même’, ‘tout à fait’, ‘ah bon ?’, ‘carrément’, ‘voilà’.
In Swedish: ‘jaha’, ‘precis’, ‘just det’, (if you’re over a certain age) the inhaled ‘ja’.
In German: ‘genau’, ‘ach so!’, ‘eben’, ‘tja’, ‘ach was’, ‘neeee’.
In Hebrew: ‘נכון’, ‘בדיוק’, ‘באמת’, ‘נו’, ‘וואו’.
Etc.
This is vastly better than hostile silence.