Sonali Deraniyagala has survived the unthinkable. In her memoir "Wave," published last week, she describes the experience and wrenching aftermath of losing her parents, her husband, and her two young sons in the 2004 tsunami triggered by an earthquake in the Indian Ocean. Of the roughly 275,000 people killed by the impact of waves that reached up to a hundred feet high, five of them made up her entire world.

It was December 26, and the family was on vacation from London at Yala, a national park on the southern coast of Sri Lanka. The book’s opening lines, so understated in hindsight, capture the ordinariness that can shift, in an instant, to pure shock: “I thought nothing of it at first. The ocean looked a little closer to our hotel than usual.”

At the time, Sonali’s husband Steve was in the bathroom, and their sons -- Vikram, seven, and Malli, five -- were on the hotel room’s back veranda playing with their new Christmas gifts. By the time she noticed the growing white froth of the sea, “Vik was sitting by the back door reading the first page of The Hobbit. I told him to him to shut that door. It was a glass door with four panels, and he closed each one, then came across the room and stood by me.”

The waves became furious and menacing, and Sonali called Steve out of the bathroom. Barefoot, she grabbed her boys by the hands, and the family ran. They ran past the door of her parents’ adjacent room without knocking or shouting to warn them. There was no time. The jumped into a Jeep, the driver pulled away, the water entered, and she never saw her immediate family again.

That Sonali survived by holding onto a branch after getting tossed and pummeled by the raging water is a miracle. That she sat down to write this book -- to communicate the physical and emotional anguish that followed, and the power of memory to ravage and to heal -- is a testament to human resilience and to the cathartic potential of storytelling. There may not be a solution, or even any resolution, to her terrible circumstances, but there are hints of renewal in the book’s arc through numbness, grief, and her grounding ability to put one foot in front of the other as she travels between their family homes in London and Sri Lanka to her new home of New York City.

We feel pity and sorrow for Sonali, as we would for any tragic heroine. But with ancient Greek drama, there is a safe distance separating us from its symbolism. When Medea, Electra, and Cassandra go mad, we shudder at the horrors of myth. When Sonali compulsively Googles ways to kill herself, drinks and drugs herself into oblivion, and smashes her head against the sharp wooden headboard of the bed in self-mutilation, her terror feels frighteningly close.

Sonali’s story might drive you to seize this day, this instant, and live the most compassionate, loving, and fulfilling life possible. You might want to share her story with anyone who has suffered any kind of loss. In reminding others that they’re not alone, you’ll also be reminding yourself. Our empathetic physical responses to the understated poetry of Sonali’s sentences -- chills that make every hair stand up, shortness of breath, tender tears rolling down cheeks -- make one thing clear: what happened to her could happen to any of us. Why it happened is a mystery.