Marcy Borders, the Dust Lady from that iconic September 11, 2001, photo, has died of cancer at the age of 42.

As with many people who were in lower Manhattan that day, Marcy Borders was caught in the worst terrorist attack on the U.S. mainland. One of the many photographers who were snapping images that will forever live in our collective memories spotted her, and she became the Dust Lady.

Covered in the ash of what used to be the south tower of the World Trade Center, Marcy Borders was almost unrecognizable in her elegant suit, which she wore to work that day. The only part of her body that did not have a thick layer of ash was the Dust Lady's eyes. She seemed to be in shock as she stared at the photographer.

According to the New York Daily News, Marcy Borders' family announced the 42-year-old survivor died of stomach cancer.

"I can't believe my sister is gone," the Dust Lady's brother Michael Borders posted on Facebook after his sister's death Monday.

On September 11, 2001, Borders came to work as a legal assistant for Bank of America without knowing that she would become part of the legacy of that day. Her office was on the 81st floor of One World Trade Center when terrorists -- who had hijacked two commercial airliners -- slammed the planes into the buildings while thousands of workers went about their day.

Marcy Borders was 28-years-old then, and was forced, along with everyone who survived the crash, to walk down the stairwell in her heels. She finally stepped onto the sidewalk, just as the tower was collapsing from the fire above, when she became the Dust Lady and her photo was seen around the world as a testament to what she had gone through.

Before the tower came down, a Good Samaritan grabbed her and pulled her into the lobby of one of the surrounding buildings. Getty Images photographer Stan Honda snapped the now-iconic photo.

After surviving the horrific ordeal, where 2,900 people were killed, Marcy Borders struggled with depression and addiction for years. She finally checked into a rehab center in 2011, she told the Jersey Journal, and remained sober. The Dust Lady was diagnosed with stomach cancer and believed it was related to her experience on 9/11.

"I'm saying to myself 'Did this thing ignite cancer cells in me?' I definitely believe it because I haven't had any illnesses. I don't have high blood pressure... high cholesterol, diabetes."

Family, friends, and even New York City Mayor Bill de Blasio have left messages of condolences on the passing of Marcy Border, who will forever be known as the Dust Lady of 9/11.

[Photo by Robert Giroux / Getty Images]