THORNTON, Colo. -- A year and a half ago, Shannon Davis weighed 525 pounds and began the toughest battle of her life.

"To be honest, I don't know how accurate 525 pounds is, because the scale only went to that," said Davis.

The first step was realizing the problem, and that came with a co-worker's kind confrontation.

"He goes, 'The team loves you. The manager loves you. I love you. Do you love yourself?'" she said. "He was absolutely right. I didn't love myself. I just lived my life for others."

It was a wake-up call, and once Davis was awake, there was no stopping her.

"First off, I had to change my diet," she said.

She also started walking at the pool, then at the park.

At first, she could barely get from her car to the sidewalk.

"But you know what? I kept coming back," she said.

And the weight was coming off.

She's lost 165 pounds and counting.

"I'm halfway there now, halfway through a journey," she said.

The next step, though, may be the toughest.

Davis plans to walk The Breast Cancer 3-Day -- 60 miles in three days -- in honor of her mother, a breast cancer survivor.

Davis points out that family history and being overweight increase her risk for breast cancer. She wants to inspire others at risk to take a step in a battle that can be won.

"You are accountable to the life that you want tomorrow today," said Davis. "Every choice and every action that you take today can influence you tomorrow."