WASHINGTON – Ex-CIA chief David Petraeus is revealing his thoughts about the extramarital affair that ended his career.

Petraeus wrote, “I screwed up royally,” in a handwritten Nov. 20 letter to a friend, retired Brig. Gen. James Shelton, the New York Post reports.

“I paid the price and sought to do the right thing at the end of the day,” Petraeus wrote.

Petraeus stepped down on Nov. 9 after his affair with biographer Paula Broadwell became public.

“He’s a superb human being. What happened to him happened to a number of people,” Shelton told the Post.

Petraeus’s letter told his friend he does not want his 37-year-old marriage to end.

“Team Petraeus will survive though {I} have obviously created enormous difficulty for us,” he wrote. “Holly is, however, once again, demonstrating how incredibly fortunate I was to marry her.”

The letter is signed “ATW” for “All The Way,” the military call for Army parachutists, the Post says.

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