According to the book, a copy of which has been obtained by The New York Times, 17-year-old Laura Welch (Bush's maiden name) was driving her father's Chevrolet Impala with a girlfriend as passenger, rushing to a drive-in movie when she ran a stop sign and hit the car being driven by her school's star athlete, Mike Douglas.
"In those awful seconds, the car door must have been flung open by the impact and my body rose in the air until gravity took over and I was pulled, hard and fast, back to earth," she writes, according to The Times. Later, she says, "I was praying that the person in the other car was alive. In my mind, I was calling 'Please, God. Please, God. Please, God,' over and over and over again."
Bush blames the accident on the fact that she and her friend were talking in the car, the road was pitch black, the intersection was dangerous, the stop sign was small and Douglas's car was unsafe.
She says her guilt was compounded by the fact that she slept through the victim's funeral – after his parents had said they did not want her to attend it. She is also sorry that she never reached out to the parents afterward, though the sound of Douglas's mother crying, heard through the thin curtain in the emergency room, has remained with her.
Since the horrific incident, Bush writes, she has encouraged young drivers involved in severe accidents to consult loved ones, counselors or spiritual or pastoral advisers, reports The Times.
On political matters, the author takes on her husband's detractors, and labels his much-criticized flyover photo-op above New Orleans after Hurricane Katrina as having been in the best interest of victims and relief workers.
Meet Sandra Bullock's baby! For the whole story – including photos of her son Louis, an emotional interview about her breakup with Jesse James and her life as a new mom – pick up the new issue of PEOPLE, on newsstands Friday