Robert Patterson asks the question in Family in America:

...the fatal flaw is that the GDP [Gross Domestic Product] leaves out the most important sector of society that makes the private and public sectors able to function: the social sector.

... Further skewing the books, every time an intact family breaks up­—which represents a huge loss to parents and especially to children—the GDP calculators, deeming that significant, suddenly turn on and count all the derivative activities of divorce as positive indicators of economic growth.

Believe it or not, every divorce, because it generates activity in the private and public sectors, boosts the GDP. That activity includes greater workloads for divorce lawyers as well as the divorce-court and child-support systems, heightened demand for second households, therapy for the children, as well as new or increased employment commitments for the mother outside the home. In fact, as a divorcing mother is often forced into the full-time labor force, she may spend relatively more money on clothes, commuting, daycare, and dining out. Even when eating at home, she may opt more for costlier prepared foods than cooking at home.

At the same time, the divorced father will increase both energy and water consumption in setting up a second household. He may eat even less at home and frequent bars more often.

The GDP rises in response to all these inputs, but the net effect is reduced happiness, the handicapping of the next generation, and a less promising economy down the road. So in the GDP universe, the destruction of a little civilization through divorce—which splits a strong joint home economy into two weaker ones—is considered good for the larger economy. But in this same distorted GDP universe, the success of married couples in maintaining a lasting union harms the economy at large.