Katherine Keith taps the tips of her pink, cracked and dirt-crusted fingers against her thumb. She has no feeling in them, the consequence of racing more than 700 miles on a dog sled across Canada's Yukon Territory and Alaska in the past eight days, and that lack of feeling is making even simple tasks difficult.

After several attempts, she finally manages to zip her coat. Her laugh at the repeated tries it takes to do so speaks to the pain she's enduring. She has to laugh or maybe she'll cry. It's 3:30 a.m., 30 degrees below zero, and now she's about to get back on the sled for another lonely ride in the Yukon Quest, a lesser-known but equally grueling (some say more so) counterpart to the Iditarod.

She aches from her ankles to her neck, but she sounds like she's having a blast. She has already bid me a good morning with exuberance far out of proportion to the actual quality of the morning -- did I mention it's 3:30 a.m. and 30 below?

"It's warming up," she says with a smile.

At first I think she's joking, but she's right: 30 degrees below zero is 8 degrees warmer than when Katherine arrived the previous night at this checkpoint in Circle, Alaska, on the banks of the Yukon River. And earlier in the race the thermometer on her sled read 55 below. So yeah, it is warming up, and it's just like Katherine to be cheerful about it.

Her parka finally zipped over her four other coats and two Smartwool shirts, she starts putting Velcro-strapped booties on her Alaskan huskies, a tedious task even in ideal conditions. It's like putting Velcro boots on a baby, only instead of two feet there are four and instead of one baby there are 11, and instead of being inside a warm nursery, she is outside in Alaska in February. She's barehanded, with fingers that have been wrecked by the cold for days already.

The danger of this cold is very real and goes beyond frostbitten finger tips. With more than 200 miles left in her first Yukon Quest, Katherine, 38, can't afford mistakes. Her body wants her to hurry, but her mind tells her to take her time and do it right. If she doesn't strap the boots on properly, the result could be disastrous, for the dogs and for Katherine. The dogs need the booties to protect their feet from razor-sharp ice, and Katherine does not want to have to stop the sled and use precious (and waning) energy to replace them if they fall off on the trail.

Starting with the dogs closest to the sled (Mozart and Shadow) and ending with the leader (her favorite, Blondie), Katherine methodically attaches the booties. Along the way, she scratches ears and rubs bellies and whispers sweet nothings to the dogs who need to hear them. She wants them to be mentally ready for the difficulties to come. She hopes she will be, too. So far in this race, the climbs have been tougher and the weather more brutal than she anticipated, and she thought both would be rough.

She entered the Yukon Quest not in spite of those difficulties but because of them. Some athletes turn to sports to escape from life. Katherine turns to sports to fight for hers. She puts herself through the mental and physical misery of training for and competing in races like the Yukon Quest and the Iditarod, which she will enter this year for the fourth time, because she sees it as a way to make herself more resilient, in racing and in life. If she can survive long nights of sleep deprivation, pain and exhaustion in the life-threatening wind and cold, she says, she will be able to draw on that experience and use it to overcome pain in her personal life.

And she's had more of that than anybody should.

After she graduated from high school in Minnesota two decades ago, Katherine rock-climbed across the United States, hiked the Pacific Crest Trail from Mexico to Lake Tahoe and worked on an archaeological dig in Italy. After a short-lived marriage to her high school sweetheart, she found herself, at 21, back in Minnesota and unhappy. She had struggled with depression and an eating disorder since she was 15, and when she drank, it was to excess. She knew she needed to change her life.

In her travels, she had been seeking a different life for herself, one she says only Alaska could provide. She longed for quiet, rugged, challenging solitude. A move there would fulfill a dream she had had since she was a young girl devouring books about homesteading, she says, while also allowing her to restart a life she had lost control of. So in the summer of 2000, she bought an old ice cream truck for $500, put a bed in the back of it and started driving.

As the vastness of Alaska grew closer, she realized she had almost no plan of what she was going to do when she got there. She had enough money to get there but not much more than that. She had no job and no place to live. "I had this sort of naive trust in the universe that synchronicity would step in and things would always work out in the end," she says.

When Katherine arrived in Seward, Alaska, her gas tank and wallet were empty. She talked her way into a job teaching tourists to kayak, though she had never even been in a kayak. Her boss let her live in the ice cream truck in the parking lot and eat from his freezer full of meat, thus ending her time as a vegetarian.

At a coffee shop, she saw an ad for a position with a dog-mushing kennel -- the type of job she moved to Alaska to get. The position offered no salary but provided room and board and the education about dogs that she wanted. She sold the ice cream truck for $2,000 and moved to a city in the Arctic Circle, one about 200 miles from the easternmost tip of Russia, called Kotzebue, population 3,272.

His name was Dave. They met ice fishing in Kotzebue less than a year after Katherine moved to Alaska. He was 6-foot-2, or so, with pale skin and a shaved head. He had a great sense of humor and loved Queen and Johnny Cash and Willie Nelson. He was from the Lower 48, like Katherine, and had visited Alaska with his parents as a boy. Like Katherine, he longed for a life of solitude, so he returned to live in the 49th state full time.

Katherine called her mom, Pat Byrne, in Minnesota to tell her she had fallen in love and invited her to fly up to meet Dave. She had never done anything like that before. "She accepted the woman in herself, and that it was a beautiful thing," Byrne says. "Dave brought the femininity out in her and just completed her."

Katherine's half-sisters through their mom lived at different times with Katherine, Dave and his son in a remote cabin in Kotzebue. It had no electricity or running water, and they all loved it. She had, indeed, left her troubles in Minnesota and started a new life. It was hard physically but fulfilling holistically.

Dave and Katherine's first daughter, Madi, was born Jan. 27, 2002. Katherine had moved to Alaska in pursuit of an unadorned life, and she had found that and a loving family, too. "They were everything that she wanted in life in Alaska," says her dad, Jim Gleason. "They had the same dream that was embodied in that relationship. It was like everything -- all the struggle, all the hard things she had to do in Alaska up to that point -- made that all worthwhile."

Within 21 months, all of that was shattered.

About a month after Madi was born, Katherine had to pick up Dave from the woodlot -- an area of trees about two miles away that they visited often to retrieve firewood, the sole means of heating their cabin. Katherine and her half-sister Cindy Foster climbed onto a snow machine (also known as a snowmobile). Foster drove. It was winter in the Arctic Circle, bitterly cold, so Katherine tucked Madi inside her parka.

On the way, Katherine looked down at Madi in her nesting place against her chest. Madi had blood in her nose and wasn't breathing. Foster stopped the snow machine. Katherine performed CPR for an hour. Foster rushed ahead and desperately tried to find Dave, or anybody else, to help. "There's no phone service," Katherine says. "No way to call for help, no EMS, no nothing."

Dave summoned a helicopter, but it was three hours before Madi arrived at the hospital. It was too late. "She died because of how I was holding her on the snow machine," Katherine says. "If I had not taken her out that day, there's a chance she would still be here."

Infants are at risk of asphyxiation when they're wrapped into slings or baby-wearing clothing -- their mouths and noses can get pressed to the adult's body, or they could end up in a chin-to-chest position, which can interfere with breathing.

But Madi was born with a hole in her lung, and it's possible that killed her, which would mean that the way Katherine held her had nothing to do with it. "It's something you never know," she says. "So it's something you blame yourself with, for always."

She also carries guilt, she says, because if she and Dave lived in a "normal" environment, getting help would have been easier. "I still have nightmares frequently about it," she says.

The couple's families made the grim trip to Kotzebue for Madi's funeral. "We didn't want them to just be left with just all the loss and the tragedy, so we picked that time, of all times, to also get married, so people had a little bit of positive ..." Katherine says, then stops. "Not positive, but a feeling of hope."

When the family left, Katherine and Dave began to piece their lives back together. They focused on trying to complete the log cabin they had been building. For a year, they cut down trees, loaded them on a trailer attached to a snow machine and hauled them back.

Tragedy struck again before they finished the cabin.

Katherine had her second daughter, Amelia, in March 2003, about a year after Madi died. Amelia became -- and remains -- a centering force, a reason to keep fighting, amid Katherine's grief, even if Katherine was terrified at the beginning that Madi's fate awaited Amelia.

A handyman, Dave was always tinkering with something, and one of his projects in the fall of 2003 was an airboat. He wasn't done with it; he had not put on the "squirrel cage," which would protect the propeller on the back from debris. When a neighbor named Diane Nelson had a medical emergency and needed to get to the hospital in November 2003, Dave tried to use the airboat to take her across Kotzebue Sound.

Dave and Nelson never made it to the hospital. Katherine was in Washington state visiting Dave's family when she got a call that he was missing. She called their camp phone 30 times, desperate to hear his voice, even though she knew she wouldn't. Nobody knows what happened. But the ice conditions on Kotzebue Sound were poor and the wind was howling that day, and somehow the airboat crashed. The boat and Nelson's body were found the next day.

Search parties looked for Dave long after any hope of finding him alive had been exhausted. For months, Katherine harbored "naive fantasies" that Dave had survived the crash, had amnesia and had wandered into a village. His body was found the following May.

Katherine tried to keep living the homestead life. But she worried another disaster was coming. One night the cabin filled with thick smoke after a cat knocked over a candle and started a fire. Katherine dressed Amelia as quickly as she could and ran outside. It was so cold the snow machine wouldn't start. She plugged it into the generator and waited in the frigid night air.

It was all too hard. The things she loved about Alaska -- the remoteness, the isolation, the ruggedness -- became not only a burden for her but a danger to Amelia.

On top of the double dose of crushing grief, Katherine was confronted with the fact that her inherent belief about how the world worked was wrong. The universe that had been so kind to her now left her life in tatters, so she stopped counting on the universe. She knew if she was going to survive her grief, she had to do something about it. Healing would not just happen on its own -- she had to pursue it.

She decided, as she had before she moved to Alaska, that she needed to change her life in order to save it. In 2005, she moved to Fairbanks and enrolled in the University of Alaska. Her half-sisters again lived with her at different times, as Katherine was now a single mom raising a baby while working full time and going to school full time. Compared to what she had just been through, it was a "piece of cake," she says.

"It was something I could focus on," she says. "I would pour myself into it and try to figure out a way to heal from the loss."

She now sees the move to Fairbanks as the first step in her own re-creation. She was, like that morning in Circle, "warming up." She discovered during those horrible, grief-soaked years that she had to learn to take risks again. She didn't want Amelia, who turns 14 this month, to be raised by a woman who spent her life hiding. She told herself: "Yes, I want to live. Yes, I want to be really proactive about this. Yes, I'm going to not be defeated. Yes. I just had to make a really big conscious effort that, yes, I'm doing this. I'm not going to let this drag me down because that disrespects their memory."

And it was more than just saying yes in a reactive way. Katherine sought out new experiences. She trained for and competed in triathlons and Iron Man competitions as a way to refill her reservoir of willpower, strength and grit that emptied when Madi and Dave died. The first Iron Man she entered was on the sixth anniversary of Dave's death. She saw it as a way to honor him and to mark another turning point in her life. She cried and yelled as she ran across the tough, hilly course near Las Vegas.

"It's a self-test to see if I'm resilient enough," she says. "You have to train your body to be able to run a marathon. But you also have to train your mind to be able to withstand the difficulties in life. By putting myself through the Iron Mans, I think in my twisted way, I was tuning up my mind to make it a more resilient place."

She sees her dog-mushing career the same way. If she could finish the Yukon Quest -- all 946.7 hand-freezing, energy-sapping, hallucination-inducing miles of it -- she would have more proof that she can survive whatever life throws at her.