They're not "made in heaven" as you say, because this implies that all marriages are successful, which is not the case. Rather, it is more proper to say that all occurrences - marriages, divorces, births, deaths, successes, failures, everything both happy and sad- are controlled by Allah swt and we should accept whatever happens as the will of allah: perhaps to make us stronger, perhaps to make us humble, perhaps to reward us for even the smallest act of kindness.
Masha Allah zabardast.