Two years ago, Liz Diamondstein was at a crossroads in her already-trying personal life.

Having beaten cancer THREE times, she now faced the prospect of a separation from her husband of nine years. Feeling overwhelmed, for the first time this resilient survivor decided to run from her problems. Literally.

"Running became my personal therapist," said Diamondstein. "Whenever I had a problem, I would go out for a run and figure things out. By the time I get home, I had my solution."

Though she's been running for over two years now, Liz Diamondstein has never entered any race at any distance until this Sunday when she'll make her way down Broad Street.

"I run for mental clarity, for peace," said Liz. "People in my neighborhood have seen me running for a couple years now, and they'll ask me to run with them. I always say no. They might think I'm cuckoo, but I think running with other people would change the experience for me."

Liz's biggest challenge began in 2004 when she was diagnosed with thyroid cancer. After multiple rounds of radioactive iodine therapy, Liz was advised by her doctors not to become pregnant. Once she was pronounced healthy, she gave birth to her son Jack late in 2006.

Six months later, the cancer was back—with a vengeance.

"That time, we decided to do a radical surgery," she recalled.

Liz underwent a complete neck dissection and had over 100 lymph nodes removed. "You can't help but wonder 'Why me? Why do I have this cancer?'" admitted Liz.

But rather than just wonder, she did research—voraciously reading available literature on diet. She decided to become a vegetarian and pursue an organic diet.

"I'd always been in shape—always healthy," she said.

But cancer and other personal challenges had taken away Liz's motivation to exercise. Compared to battling cancer and going through various divorce hearings, running was a snap.

"Going through my separation and divorce was a challenge unlike any other," she said. "So every time I went to a hearing or filed a motion, I'd increase my mileage. One challenge sort of led to the other."

Starting with a walk around the block, Liz quickly progressed to running a few blocks on each walk. This seemed easy, so next she increased the run to a mile. Before long, she was running daily at distances of three, then five, then eight miles—all the way up to the 10-mile distance of Broad Street.

"My dad, George Ardelean was a retired Philadelphia police officer in the 23rd District," said Liz. "His beat was right along Broad Street. He passed away a few years ago, so I'll have his memory to carry me through a big portion of this race."

Of course, running is nothing without a little extra motivation. Here's where Liz Diamondstein finds hers:

"My ex-husband ran Broad Street last year, and he's running again this year," she revealed, "so this is my chance to get out there and beat him!"

"I'd say he's about one minute per mile faster than me," she admitted. "But I'm out there running every day because all I want is to see my name above his."

Don't bet against it. Liz Diamondstein has quite a history of beating the odds.

Liz's thoughts on Boston: "That was just devastating. I've been thinking about it ever since, and my thoughts go out to all the families. I just think about how great I feel as I finish a run, and to have that excitement taken away in that fashion? It's horrible."

Read more Sports Doc for Sports Medicine and Fitness.