The housing market has remained at the center of the nation’s economic troubles throughout 2010. The housing market started the year flat on its back, and it’s ending the year in nearly the same condition. Home sales are still depressed, home-building remains near a 50-year low, and home prices are still about 30 percent below their peak. Part of the problem this year has clearly been high unemployment. But the ongoing foreclosure crisis also keeps glutting the market with unsold homes. Meanwhile, the government’s efforts to prevent foreclosures over the past year were a pretty big disappointment to many people.