Compiled and updated from earlier reporting by TheStreet.com.Countrywide Financial's ( CFC) shares have taken another severe hit this week amid rumors that it was preparing to file for bankruptcy. Countrywide, which has struggled since the summer in the face of a significant pullback in the mortgage sector, accounts for around 20% of mortgage origination in the U.S. Should Countrywide file for bankruptcy, it would further roil a U.S. market that has been deeply stung by a slumping housing market after a heady boom in mortgage origination and homeownership. Whether or not the nation's largest mortgage lender is too big to fail remains to be seen. Countrywide is not alone with its troubles. Dozens of other mortgage lenders that cater to borrowers with less-than-stellar credit are in a similar fix. This raises important questions for borrowers: What do you do if your mortgage is with one of these sinking companies? Or worse, what if you're in the midst of the application process and find out your mortgage company is shutting its doors? The crucial thing for consumers to know is that they are still required to make their principal and interest payments, regardless of what happens to their lender. In the case of Countrywide, mortgage servicing -- a unit that works with borrowers to ensure timely payment -- continues to be a significant component of the troubled-lender's operations, generating consistent fee income.