What is the religiously prescribed duty of a husband towards his mother, who is psychologically distressed by his wife's estrangement from her, knowing that the wife fulfills her other duties and lives in the same house?

The husband must advise his wife to abandon the forbidden boycott, and she must obey him in that, especially since the wife is not obligated to live with or serve her husband's mother according to Sharia, and this will reduce disputes. The husband should please his mother by being kind to her, and not fall short in his wife's rights. He should advise her with gentleness and kindness regarding what he asks of her that she is not religiously obligated to do.