We also should account for the fact that berating people to stay committed to their marriage, while their acquaintances are divorcing, is fruitless moralizing.

If people see parallels between the lives of the people divorcing their own lives, they will be inclined to follow suit. That is why divorce tends to be "contagious".

Better would be, if they saw fewer commonalities and could view the divorces as "weird, personal unfortunate" incidents. That requires removing such commonalities.