Susan Spencer-Wendel never stopped writing.

Even in her last months, when she couldn’t type or talk, her mind remained alive with words. She wrote poetry in her head, repeating the syllables over and over to herself so she could “hear” them and remember them.

“I will write until the day I die,” she often said. And so she did.

Ms. Spencer-Wendel , a journalist so tenacious she managed to tap out her life story with one thumb and turn it into a best-selling book, “Until I Say Good-bye: My Year of Living With Joy,” died Wednesday morning at her home in Lake Clarke Shores of amyotrophic lateral sclerosis, or Lou Gehrig’s disease. She was 47.

In the end, the muscles of her body could do almost nothing – yet, somehow, she could still smile. And laugh.

When she was diagnosed in June 2011, she made her lifelong best friend, Nancy Maass Kinnally, promise: “We will laugh more than we cry.”

This gift – the ability to stay content in the face of death — is the lesson of her memoir.

“Live with joy. That is the fundamental message,” she said in March 2013, shortly before the book was released. “Set your intention – and do it. And accept nature. No matter what happens to you, accept nature.”

‘Most Likely to Succeed’

Ms. Spencer-Wendel grew up sun-kissed, athletic and popular – the peppy drum major of Forest Hill High School’s Class of 1984. She was a straight-A student, too, voted “Most Likely to Succeed. ”

In her memoir, Ms. Spencer-Wendel acknowledged that her likelihood of success was surely boosted by her mother and father, Tee and Tom Spencer, who adopted her shortly after her birth in Fort Lauderdale on Dec. 28, 1966. They infused their blond-and-blue-eyed bundle with discipline and duty and a love of the water.

Raised in West Palm Beach, where her dad owned Lewis Pharmacy and Sims Pharmacy, Susan became little sister to Stephanie, who was two years older. She dedicated her book to Stephanie, “whom God divined to be my sister.”

She found her lifelong best friend – Nancy Maass Kinnally – in seventh grade at Palm Beach Public School.

They had the same silly sense of humor, Ms. Maass Kinnally says, with Nancy providing a bit of balance to Susan’s natural exuberance.

“I was a little more nerdy and had more angst,” Nancy says, “and she was a bit more free-spirited and mischievous.”

They filled their junior-high days with cheerleading, band and the swim team – and goofy pranks. Susan admitted in her memoir she was “quasi-incorrigible” and once turned back the clocks at school so they could go to lunch an hour earlier.

“We would have our parents drop us off at the movie theater at the Palm Beach Mall to see a PG movie,” Ms. Maass Kinnally recalls, “and then Susan would try to crawl across the floor in front of the snack counter and slip into the R movie without being spotted, while I slinked behind her worrying about getting caught.

“That was the sort of innocent mischief we used to get into that made us feel like a couple of outlaws and would have us rolling with laughter.”

They headed to college together – the University of North Carolina at Chapel Hill – and it was Nancy who encouraged Susan’s love of travel and discouraged her from going into pre-med.

She told her, “Susan, that’s not you.”

What Susan was: a writer, a journalist, a crusader for justice.

She got her master’s degree in journalism from the University of Florida and embarked on two major life changes in the early 1990s: She married John Wendel, the handsome lifeguard she had met over summer vacation at the Lake Lytal Pool in suburban West Palm Beach, and she headed with him to Budapest, where John had a teaching job and Susan became managing editor of the fledgling “Budapest Sun.”

Their two years in Budapest were among the best of their lives, Ms. Spencer-Wendel writes. “Those days, those adventures together, bonded us. Like glue on a piece of furniture, they were the invisible underpinning that held us together for a lifetime.”

The couple moved back to Florida in 1994, then to Colombia to teach for a couple of years. But when their oldest child, Marina, was born in 1997, they headed home for good.

Ms. Spencer-Wendel became a staff writer for “The Palm Beach Post,” covering courts.

She worked 50-hours-plus a week, jostling major court cases with motherhood. (Son Aubrey arrived in 2001, and Wesley was born in 2003.)

She reported on dense legal issues, poking holes in the reliability of eyewitness testimony. Her reporting revealed that almost 75 percent of prisoners exonerated by DNA had been wrongly identified by an eyewitness. At least one man’s conviction was overturned – and the Palm Beach County Sheriff’s Office and, later, the state changed guidelines for eyewitness identification.

So dogged was her courts reporting, she once even tracked down a hired assassin.

“Susan was an incredibly hard-working and gifted journalist who truly made a difference with every story she wrote,” Palm Beach Post publisher Tim Burke said. “However, the greatest gift she gave all of us was the inspirational example she set.”

In September 2012, the Florida Bar presented her with its lifetime achievement award, lauding her “willingness to look beyond the bare facts to understand the lesson behind the story.”

When ALS forced Ms. Spencer-Wendel to give up her job as a reporter, she cried as she wrote her resignation letter:

“It was a privilege to go to work each day and grow democracy, to ferret out stories no one wanted told, to be trusted to inform and, yes, entertain our readers. When someone would ask me: ‘who sent you?’ I loved to reply: ‘Well, ma’am, that would be Thomas Jefferson.’”

‘Until I Say Good-Bye’

Understanding the lesson behind the story was always Ms. Spencer-Wendel’s gift – even when it came to her own story.

When she knew she would have just one year of good health left, she decided to take special trips with her dearest loved ones, to make memories and experience “a year of living with joy.”

She took seven journeys with seven people and wrote about two of those trips in “The Palm Beach Post” – a trip to the Yukon with Nancy, to see the Northern Lights. And a return to Budapest with John, to celebrate their 20th anniversary.

Those stories led to a contract from HarperCollins – who paid her $2 million to write her memoir, with the help of collaborator Bret Witter. Universal has purchased the movie rights, and screenwriter Sarah Treem calls Ms. Spencer-Wendel “a true female hero.”

Ms. Spencer-Wendel was determined to write about strength, not sickness. To leave her children a legacy and a lesson: Life is yin and yang, good and bad — and you have a choice in how you handle life’s blessings and burdens.

She typed a 362-page book in three months using just her right thumb – by tap-tap-tapping on an iPhone. It reached No. 3 on The New York Times best-seller list.

“Accept the life that comes,” she wrote. “Work and strive, but accept. Don’t force the world to be the one you dream. The reality is better.”

As she accepted the reality of her illness – the knowledge that all her muscles would fail her, one by one – she moved from panic to peace, from hurtling through her days to appreciating every small moment.

She found serenity in Buddhist philosophy:

“Be content with what you have; rejoice in the way things are.

When you realize there is nothing lacking, the whole world belongs to you.”

‘Look for me in the sunset’

Ms. Spencer-Wendel tapped out her memoir from the chickee hut in her backyard, a tropical haven with comfy couches and twinkling lights.

Her chickee hut was her refuge, her heaven on earth, the place where she wrote and greeted friends and family and watched her dogs Gracie and Lenny frolic across the yard.

There, under the palm-frond roof, she contemplated the whole journey of her life – her relationships with her family in West Palm Beach and also her new friendship with her birth mother, Ellen Swenson, and the family of her late biological father, Panos Kelalis, a doctor and a Greek Cypriot who died without knowing he had a daughter. After discovering the story of her birth parents in 2008, she traveled to Cyprus to meet her birth father’s family.

They used one word over and over to describe Panos: “Fearless.”

He would go out of of his way to help people and stare down any challenge, they said.

“I took the word into my soul,” she wrote. “Fearless was in my genes.”

She thought about all this as her ALS progressed, snuffing the energy from her body yet focusing the energy of her mind.

“The first time I sat in the finished hut, I listened to the wind rustling the leaves, the pool waterfall nearby, our wind chime tinkling,” she wrote. “I could stay here forever.”

This is where she sat on a sunny day in the spring of 2013, when her husband John positioned her just so on the couch pillows, translated for her when her speech was hard to understand and made sure she had coffee in her special tumbler – the one personalized with the words “Susan’s Wine Glass.”

Ms. Spencer-Wendel smiled and whispered to her guest: “I love him.”

And this is where she sat with Nancy on her last birthday, Dec. 28, when they talked about how different their lives would have been if they had never met each other, how different it would have been if Susan had never been given up for adoption, if she had grown up with her biological parents.

They talked about how comforted Susan felt, knowing that John and Stephanie and Nancy would be there to shepherd her children as they grew up, to remind them when they missed her to “look for me in your heart…look for me in the sunset…sense me there and smile.”

They talked about the twists and turns of life, the yin and the yang, the “twinning of good fortune and bad fortune.”

Susan asked Nancy to make another promise: Please never worry about the small things. Please nurture our garden of memories.

And always, always, laugh more than you cry.

Susan Spencer-Wendel is survived by her husband, John Wendel, and their three children: Marina, Aubrey and Wesley; her father, Tom Spencer (her mother, Tee, passed away in March); her sister, Stephanie Harwood Parlamento (husband Don) and her sons William and Stephen Harwood; her grandmother, LaFon Spencer; John Wendel's parents Richard and Janet; John's brother Jay (wife Nicole) and daughters Anna and Ella; John's sister Karen (husband Bernard) and son Anthony; her uncles David Spencer (wife Jackie) and Jacky Spencer and Aubrey Motz III (wife Marilyn); her aunts Beth Adams (husband Robert), Ramona Motz and Martha Sue Fox (husband George); her cousins Terry Davis, Mona Bibby (husband Mike), Tanya Gore, Frank Spencer and Tony Spencer (wife Melanie); her biological mother, Ellen Swenson. She is also survived by Nancy Maass Kinnally, her "beautiful best friend for life."

A party to celebrate Susan's life will be held in a couple of weeks, and details will be announced. The family asks that donations be made in Susan's name to the ALS Association at alsa.org.