Editor's note: Jessica Yellin is CNN National Political Correspondent. She covered the John Edwards campaign in 2008.
(CNN) -- The loss of Elizabeth Edwards shouldn't be shocking. We knew she had breast cancer. We knew it spread to her bones. It's remarkable she survived for so many years. But people who never met Elizabeth Edwards tell me they're taking the news hard. It seems that's because for years Elizabeth Edwards has been one of the nation's most public survivors.
When she first came on the public stage, we knew Edwards as a mother who survived the loss of a child. Her son, Wade, died in a car accident when he was a teenager. Rather than shrouding that tragedy in silence, she talked openly about it.
She was the woman who would laugh through pain. She talked about her decision to have more kids in her late 40s and early 50s, then joked about her battle with weight. She was the unusual political wife -- self deprecating, sometimes messy, seemingly a regular gal.
Then came another tragedy. At the end of her husband's 2004 bid to become the Democratic vice president, she felt a lump in her breast. Doctors told her it was cancer. She declared that she wouldn't be defeated. She told Larry King "I just have a belief that I am going to beat this. Every indication is that all the news I've gotten really has been good news, so I feel pretty confident. I'm making those plans for the next 40 years."
Family friends say she chose the most aggressive treatment possible. She wanted to fight. And she did beat it for many years. She went on to live an incredibly active life advocating for health care reform in Washington and around the country. She wrote a book about finding strength in your darkest moments and it became a best seller. She became a role model for others -- especially women -- who suffered loss, demonstrating how to stand and fight rather than succumb to victimhood.
Even if you didn't like Edwards' politics, it was hard not to admire her grit and her feisty attitude. Toward the end, some Edwards staffers leaked stories about how difficult she could be. As a reporter you could tell she was tough.
I covered the campaign, and if you asked John Edwards a pointed question he'd take it with calm, maybe even a smile. But if you looked over at Elizabeth Edwards you could see she was stewing, seemingly making a mental note of which reporter was being hostile to her husband. She was the fierce protector.
It all made the last years of her life seem so... well, grim. It's hard to wrap your mind around what she endured. First there was the news that her cancer was back and it had spread to her bones. Then she learned her husband had an affair. Next she discovered when he told her it was over, he was lying.
Eventually she learned the man she'd been married to for 30 years had fathered a child by the other woman. All this news came as she was keeping up public appearances during a presidential campaign, constantly by her husband's side. She was his chief endorser and a key adviser. She kept up a hectic schedule. And through it all doctors were telling her the cancer was spreading.
One family friend said today, "This is so hard because Elizabeth was the survivor. Of all of them she was the tough one. She's the one who always said we'll get through it, it'll be OK. It's hard to believe she lost her fight."
She fought to stay here with so much spirit. Perhaps her legacy will be the lesson she's taught so many of us -- that even when the worst happens you can find the inner reserves to face it with grit and fight.
The opinions expressed in this commentary are solely those of Jessica Yellin.