Divorce causes a decrease in wealth that is larger than just splitting a
couple’s assets in half.  By the same token, married people see an increase in
wealth that is more than just adding the assets of two single people.
On the other hand, divorce can devastate your wealth.  Divorce
drops a person's wealth by an average of 77%.  Contrary to popular belief,
the research shows that the wealth status of divorced women wasn’t
significantly worse than that of divorced men, in terms of real money.
If you really want to increase your wealth, get married and stay 
married.   - Jay Zagorsky, Ohio State,  Journal of Sociology, Jan 2006