As a biographer to Gen. David Petraeus, Paula Broadwell enjoyed tremendous access to the general during the year they spent together in Afghanistan, finding out the idiosyncrasies that helped shape the man who was the public face of the war.
"He was really motivated to please his father when he was younger," Broadwell told ABC News' Christiane Amanpour earlier this year. "His father doled out what he called gruff love, so he was always working hard to keep his father happy and I think that's reflected in his personality now."
It was clear in interviews Broadwell gave to promote her book, "All In: The Education of General David Petraeus" that she and the general shared a mutual trust. What remained unseen, however, was an extramarital affair that sources say was discovered by the FBI after intimate emails sent from the CIA director were found in Broadwell's email inbox.
WATCH: Paula Broadwell interview on "Around The World with Christiane Amanpour"
By all accounts, Broadwell seemed to have it all.
The 40-year-old resides in Charlotte, N.C., with her husband, Dr. Scott Broadwell, who works as a radiologist, and their two young sons.
Growing up in Bismarck, N.D., Broadwell was the high school valedictorian and homecoming queen.
She went on to attend West Point, where she was ranked No. 1 in overall fitness in her class. She spent some time in the Black Ops and later earned post-graduate degrees from Harvard and King's College in London.
On Monday, just days before before Petraeus would step down from his post with the CIA, a story by Broadwell was published on Newsweek's website titled "General David Petraeus's Rules for Living." No. 5 is notable in light of the news about his extramarital affair.
"We all will make mistakes," he said. "The key is to recognize them and admit them, to learn from them, and to take off the rear-view mirrors -- drive on and avoid making them again.""
Petraeus resigned on Friday, citing personal reasons and an extramarital affair.
"Yesterday afternoon, I went to the White House and asked the president to be allowed, for personal reasons, to resign from my position as D/CIA," he said in a statement. "After being married for over 37 years, I showed extremely poor judgment by engaging in an extramarital affair. Such behavior is unacceptable, both as a husband and as the leader of an organization such as ours. This afternoon, the president graciously accepted my resignation."