(CNN) Jill Biden is married to one of the country's most well-known and gregarious politicians, but in many ways, she's the opposite -- a reserved introvert who admits being a political spouse has not come naturally.
She is deeply devoted to her family, a trait displayed early in life when she punched a neighborhood bully in the face for teasing her sister. She is strong-willed and independent, obtaining a doctorate at the age of 55 and balancing a teaching job at a community college with the demands of being second lady.
She's a mother and grandmother still struggling with the immense loss of her eldest son, an experience that has tested her faith.
This portrait of Biden emerges in her new memoir, "Where the Light Enters." The book, to be released May 7, is not inherently political. Biden does not offer insight into the 2020 presidential run of her husband, former Vice President Joe Biden.
But in an interview with CNN on Monday, Biden said her husband's ability to unify the country is why he's running for president.
"For the past two years, everywhere I've traveled across this country people are coming up to me saying, 'he's gotta run, he's gotta run, Joe has to run.' I really take it into heart and have thought about it," Biden said.
Asked how she and her husband plan to address attacks on her family from President Donald Trump, she revealed that the whole Biden family -- including children and grandchildren -- have discussed it and will try hard to ignore it.
"I don't think we're going to address, I mean we're not going to take his bait," Biden said, though she also admitted it will be hard to resist responding.
In her memoir, Biden provides an intimate look at her upbringing and marriage -- detailing her merging with a young family coping with extreme loss and her experience maintaining her own identity as she became a mother and wife to a very public figure.
The book is as much a look at Biden's personal story as it is an intimate reflection of her marriage to Joe Biden, including their gestures of love, like a book of poems he wrote for her as a recent Christmas gift and extravagant displays of affection she has arranged for him on Valentine's Day.
She writes of their personalities, "In many ways, Joe's temperament and mine complement each other. He tends to pull me out of my shell, and I help keep him grounded. He's affectionate enough for both of us. Even now, his staff members laugh about it, joking that the answer to 'Where's the vice president?' is always 'Well, where is she?'"
For Jill Jacobs, marrying a politician was never part of her plan. After the collapse of her first marriage, she committed herself to finishing her college education, writing, "I let go of fairy-tale endings, and I tried to reconnect with the brave person I used to be."
In 1975, a young Sen. Joe Biden called to ask her on a date after seeing a picture of her in a local advertisement. His brother, Frank, was an acquaintance of Jill's and got her number through friends.
"Not only had I not expected a random call from Joe Biden, but I could never have imagined he would make that call to ask me out," she writes. "I've been asked if I was starstruck by the fact that a U.S. senator thought I was worth a call, but I honestly wasn't. I was flattered that someone I'd heard of was interested. But at the time, I still wasn't 100 percent sure what a senator did exactly."
The couple dated for two years before she agreed to marry him -- a proposal he made five times before she said yes. But their relationship was not just between two people but also between four as she quickly grew close to his sons Beau and Hunter.
"From the beginning, the boys were so loving and so welcoming," Biden told CNN. "Joe wanted his family to be whole again. I think the boys wanted a mommy. They wanted the family to be whole again too. It just all worked. I tell people, it just worked so naturally. I knew it was just meant to be."
Biden also reveals in the book a chance encounter she had with Joe Biden's first wife, Neilia, at the victory party for then-Sen. Biden in 1972 -- weeks before a car crash claimed Neilia and the Biden's 13-month-old daughter Naomi's lives.
"We were there in the crowd in the Gold Ballroom at the Hotel DuPont," Biden told CNN. "Neilia walked through the crowd, and I walked up and shook her hand and said congratulations. It was a brief encounter. I didn't even see Joe that night or talk to him or shake his hand."
"She gave me such a gift," Biden added. "I got her three boys so I always felt during our marriage that I needed to honor her memory. It was important for the boys to remember their mother."
Joining the family was an adjustment, including the way the immediate and extended family interacted with each other.
"I realized that physical affection played an important role for his entire family," she wrote. "Being thrust into this group was a strange and uncomfortable development for me. I wasn't used to public shows of affection."
Asked about the women who have come forward to say her husband made them feel uncomfortable by the way he interacted with them, Biden said Joe Biden got the message "loud and clear."
"Joe has heard to back off and give people their space," she told CNN. "He has now taken responsibility for that. Someone asked me, 'Did this ever happen to you?' I have to say, it has happened to me, 20 years ago, and I did not have the courage to speak up then and say, 'Stop that, you're in my space.' Now I would have the courage, but 20 years ago I wouldn't."
"Times have changed," she added. "We have to honor, it's so hard to come forward, to have the courage to come forward and speak out. I think that's a good thing that has happened."
The Biden family's grieving process after Beau Biden's death from cancer in 2015 played out in the public eye with the loss ultimately impacting the former vice president's decision not to run for president in 2016. Joe Biden often grows emotional at public events as he talks about his son and his family's journey to cope with loss.
But in her new book, Jill Biden offers rare insight into her own grieving process, writing, "Since Beau's death, I'm definitely shattered."
"I feel like a piece of china that's been glued back together again. The cracks may be imperceptible-but they're there," she writes. "Look closely, and you can see the glue holding me together, the precarious edges that vein through my heart. I am not the same. I feel it every day."
"Am I able to feel happiness? Yes, definitely. But it's not as pure; there's just not the magic to life that I used to feel," she adds. "You'd think after all this time, I might have learned something about survival from a man -- from a father -- who couldn't be taken down. But here I sit, waiting for healing I fear might never come. Joe promises me it will."
Speaking about Beau's death in an interview with CNN, Biden said, "I don't think any mother who has lost a child is ever the same."
Biden also presents a rare look at her spiritual life, revealing she's struggled with her faith in the wake of Beau's death.
"One of my last true prayers was one of desperation, as Beau began to slip away from us, and it went unanswered. Since then, the words don't seem to come," she writes. "The beautiful stained-glass windows I once loved, the warm wooden pulpits, the rich red kneelers -- now I can see only cold colored light that refuses to shine on him, his unspoken Rosary, an empty space at the Eucharistic table."
She later writes, "And one day, I hope I can salvage my faith. I'd like to be able to pray the way I once did. So many people in my life need prayers, and I feel like I owe that to them. After all, in heaven, we feed each other."
While Joe Biden is engaging and boisterous on the campaign trail, those traits don't come as easily to Jill Biden, who writes, "I was never a natural as a 'political spouse.' As an introvert, I preferred to stay in the background."
"I was much quieter and more reticent to engage, so when strangers approached me at events, I had a hard time leaving my reserved self behind. This is a dilemma faced by any introvert married to an extrovert, but here it was magnified because of Joe's position, " she writes. "There was no denying we made a picture-perfect Christmas card, but in truth, I rarely felt as confident as I tried to look. I, too, scoured the magazines looking for dieting and makeup tips. I too, wondered if I was pretty enough, successful enough, a good enough mother. I felt inadequate at times, in the way that women are often condition to do."
Though she admits she "struggled to channel the easygoing demeanor that people can connect with," Biden says she worked to improve on the campaign trail, practicing and enlisting the help of a professional speaking coach.
"I forced myself," Biden told CNN in an interview. "I knew I had to get used to this life. People were taking my reticence as a little bit of arrogance and it wasn't that at all. I was just shy. I was introverted. But I thought, if I'm gonna be out there with him, I've got to be the one to approach people. That's what I started to do, I forced myself to do it."
Biden also writes in her book about other adjustments she had to make as second lady, including how to fight with her husband without drawing the attention of the Secret Service by "fexting."
"So when you're in the car with the Secret Service, they hear, I mean they're not supposed to listen to everything, but they're sitting in the front seat and the back seat. So of course, I love Joe to death but sometimes if he annoys me I start fighting over text," she told CNN in an interview.
"So I came up with that word, 'fexting.' Fighting over text," she added.
As her husband seeks the Oval Office, Biden said she and her husband have leaned on the Obama's for advice.
"I talk to Michelle," she told CNN. "I'm not gonna tell our conversation, but I did seek her advice. I know Joe has sought Barack's advice. That was one of our, I think the best things about our administration is we really grew to love and respect one another."
Biden also writes in the book why it was so important for her to teach as she raised her children and served as second lady, writing "teaching is my internal compass; I can always count on it to steer me in the right direction." And she shares other ways she has used her public platform to help others, including starting the Biden Breast Health Initiative and her work with military families.
She told CNN that if she becomes first lady, she will continue teaching if it's possible.
"If I could, I would. I don't know whether it would be advisable because of security reasons, but I'd love to, are you kidding?"