Speaking in an interview with "Good Morning America" co-anchor Robin Roberts that aired Monday on the show, Davis said the book, "Forgetting to Be Afraid," was intended to give people insight into her.
"You're running for governor. And people are going to question the timing. ... Are you trying to pull at the heartstrings, people are going to say, of the voters that you're trying to win votes with sympathy?" Roberts asked.
Davis replied: "I wanted to share a book about my life, how I came to be who I am. I wanted people to feel like they're not alone … The struggle of being a single mom. The struggle, after my parents divorced, and that I came through it. I came through it, through my faith in God. I came through it because of my education.
"I wanted to be very honest in my story, and not leave pieces aside," she said. "I wanted people to understand."
'She Almost Took Her Life And Ours'
In the memoir, Davis reveals that after her parents divorced, her mother became so depressed that she almost killed herself and her three children, Davis included.
At the time, Davis' mother was in her 20s with three children aged five and under.
She became depressed after Davis' birth and, after the separation, her husband remarried. Davis' mother was all alone.
"She almost took her life and ours," Davis told Roberts.
Her mother put her children in the trunk of the car because "she couldn't imagine leaving the world and leaving us behind ... she had intended to start the car in the garage," Davis said. "And an angel came into our lives that day. A neighbor who had never come to our home before rang the bell. And he sat in the living room. He held my mother's hand. He talked to her for quite a long time. And by the time he left, she was through it. And she came and collected us from the car and put one foot in front of the other and pushed on for all of us, and did a beautiful job of it."
Davis, 51, credits her mother's life experiences for giving her the strength to persevere in the face of her own challenges of being a single working mother.
The mother of two daughters talked with Roberts about her headline-making filibuster last year. Dressed in a pair of pink sneakers, Davis went on for nearly 13 hours against a bill in the legislature. Although her filibuster succeeded in delaying the restrictions, they were eventually implemented.
"For me, it was very important to give voice to the women and men that I stood for that day. ... And of course I couldn't help but reflect upon my own journey," she said.
Two years later, Davis was pregnant again with a daughter she and her then-husband, Jeff Davis, had already named, but a routine exam detected a serious problem.
"Our baby had a severe brain abnormality -- one that was such an extreme abnormality that we were told she would likely not survive to term," Davis told Roberts. "If she did survive to term, she likely would not survive delivery. And if she did survive delivery, she likely would be in a vegetative state."
Davis and her husband decided that "the most loving thing that we could do for our daughter was to say goodbye," she said, adding that the decision was difficult and made with love.
"Her name was Tate Elise Davis," Davis said. "And we loved her as we love our living daughters, Dru and Amber. And she forms, of course, a very important part of my life."
Asked by Roberts whether she could understand that some people would say they would have handled the matter differently, Davis replied: "This was how my family confronted this tragic experience. I respect so much that people make their own decisions, and that that decision is the one that is right for them."
"Forgetting to Be Afraid" goes on sale Tuesday.