Anu Aggarwal was driving home from a party on a rainy night in Mumbai, India, in 1999 when her car ran off the road, flipping and smashing into a sand dune. The wreck left the then-30-year-old Bollywood star’s car totaled, her body broken in at least a dozen places. She’d lie in the hospital in a coma for 29 days.

Nine out of 10 people in her condition end up dying, she says — but somehow Aggarwal defied the odds to make a full recovery, a journey she chronicles in “Anusual: Memoir of a Girl Who Came Back From the Dead” (HarperCollins, out Tuesday).

“I’m fortunate enough to be a miracle,” says Aggarwal, now 47, who spent months in rehab relearning how to perform basic functions. “I left the house the last night [before my accident] not knowing that I wouldn’t come back to that house for a couple of months, and when I did eventually come back, I wouldn’t know the house was mine, or I wouldn’t know my name, or my mother, or that we were on a planet and what that means,” Aggarwal says. “Nothing.”

But the crash, as physically devastating as it was, forced her to re-evaluate her life.

From the late 1980s to 1995, Aggarwal was one of the brightest young Bollywood stars in Bombay. She got her start modeling in Paris and New York, and her career took off when she starred in “Aashiqui,” a blockbuster Bollywood film loosely based on Aggarwal’s life (she played the main character, also named Anu). The movie made her an instant household name in her native India.

But from the beginning, she says, she felt uncomfortable in the limelight. “For me, one foot was always out of the glamour world,” she says. The more built-up her public persona became, the more disconnected from herself she felt.

“When I was at the peak of my career, when I was materially richest — that was the poorest time in my life [emotionally],” she says. “I had never known that kind of unhappiness before in my life.

“That’s where the purge began — [I had to decide] what was real,” she explains. “At that time I started saying, ‘Who is Anu? I don’t know who she is anymore.’ ”

So she wrapped up her last movie and made a clean break, traveling around the world for two years until she landed at an ashram back home in India in 1997. She studied yoga full time at the ashram for the next two years, learning poses and breath and studying ancient texts. She thought she had turned her life around.

‘When I was at the peak of my career, when I was materially richest — that was the poorest time in my life [emotionally].’ - Anu Aggarwal

But six months after she left the ashram, she found herself in the hospital, smashed to pieces from the car crash. “I’m a firm believer in the fact that there’s a time [for everything] and things happen as they are meant to happen,” Aggarwal says. “This accident was just pushing me forward to get me to my real purpose in life.”

Her recovery was brutal. Once she was out of her coma, her body had to heal itself from a broken collarbone, ruptured bladder and fractured ribs, among other injuries. After months of bed rest, she began to treat herself with yoga, starting by wiggling her toes. “I immediately prepared myself a program, because the doctors had given up on me,” she says. She credits her yoga training with making a full physical recovery — a three-year process, she says.

Her mental recovery was even more extraordinary — the accident had erased her long-term memory. “I had a brain bleed and a skull fracture. I had gone completely blank; I didn’t have a past,” she says. “I started life all over again, like a child. For me, it was like discovering Anu.” She calls the life she’s lived since the accident her “second life,” and she had to learn about her life pre-crash by reading her journals. “I didn’t remember a lot about my movies at all, actually . . . When I look back, I think, ‘Wow, what a life!’ ” she says.

In the 17 years since, she’s started an organization that works to bring yoga to children. “I have completely funded myself, and feel blessed to be able to do that,” she says. She travels as frequently now as she did when she was a movie star, bringing her particular method of yoga — called AnuFun, with a focus on enjoyment and laughter — to Austin, Texas; Ixtapa, Mexico; Barcelona, Spain; and throughout India (she still lives in Mumbai) over the past six months. Next month, she’ll head to Germany to collaborate with a neuroscience company on developing a yoga program. She’s single, but devoted to her work: “It’s not about having a family or having children. I’m not tied up with that at all,” she says.

She’s finally found happiness, she says, in working for others. “It’s not like I’m saying, ‘I’m going to better the world.’ That’s too lofty of a goal,” she says.

“Instead I’m saying, ‘What more can I do than I have done?’ ”