Nationwide, USA - A volatile relationship may trigger a divorce. But volatile financial markets are playing a big role in the way couples split their assets.

While their lawyers spar, a couple's retirement savings and other assets—cash, businesses, pensions, stocks, bonds, alternative investments and stock options—are yo-yoing wildly in value, turning a relatively straightforward exercise into something resembling nailing Jell-O to a wall.

Then there's the house. Often the biggest asset a couple owns, it has in many cases become their biggest liability. About one in five U.S. homeowners owe more on their mortgages than their homes are worth, and $7 trillion of homeowners' equity has been lost since 2005.