Health and Human Services Secretary Kathleen Sebelius testified before the House Energy and Commerce Committee about the troubled launch of the Healthcare.gov website in October 2013. - 

Kathleen Sebelius, the secretary of Health and Human Services, says the government is making "tremendous progress" toward fixing what she called a broken health system. 
Sebelius commented Friday after President Barack Obama announced her resignation and says he will nominate Sylvia Mathews Burwell, the director of the Office of Management and Budget, to replace her.

Sebelius's departure comes as the Obama administration seeks to move past the woes of the initial rollout of Obamacare, which included a website launch marred by glitches, an unexpected cancellation of some Americans' individual health insurance policies and seemingly endless delays of key deadlines and requirements.

Sebelius faced a high-profile grilling in front of a Congressional panel over the botched rollout of Healthcare.gov, and mentions of her all but disappeared from the President's public comments and addresses regarding the ACA. Most notably, Sebelius did not even appear at President Obama's triumphant announcement of 7 million Obamacare enrollees in the White House Rose Garden last week.

According to The New York Times, Sebelius approached the president last month about the decision. Sebelius was previously the governor of Kansas, until she was nominated for the cabinet position in 2009.

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