Any divorce is metaphorical adultery. And divorcing one's partner causes his or her adultery. When a woman is suddenly given divorce papers, her home, her children, her family, and her life expectations are all horribly adulterated. And this is also true for the man when his wife divorces him. If this is the meaning of the metaphor in both texts, we have Jesus making a plain statement of fact.
Divorce causes the adulteration of a marriage.
For others in the family and their circle of friend there will be sadness, but condemnation is never a useful activity among Christians. And we should never use these texts to condemn a person who did not relish the idea of breaking up a marriage. Some women with abusive, violent, irresponsible, or alcoholic husbands have to choose separation and divorce for their own protection and that of their children. We also note that in Matthew's Gospel there is an exception for unfaithfulness. Whoever divorces his wife, except for unchastity, and marries another commits adultery.