In 2014, Leaphart was a happy single mother living comfortably in Biloxi, Mississippi, with her four adopted and four biological children. Then one night, everything changed.
"I suddenly woke from sleep and heard the voice of God telling me I have cancer," Leaphart, 49, tells PEOPLE.
Convinced that what she heard was a real message from a higher power, she immediately went to see her doctor for a mammogram. The mammogram came back negative and the doctor told her to come back for another test in six months.
"I'll be dead in six months," she replied.
At her insistence, the doctor performed a second test – and that's when he saw the tumor. Leaphart's instinct was right.
She was diagnosed with an aggressive form of breast cancer, which resulted in an immediate bilateral mastectomy without possibility of reconstruction. The surgery left her with two large scars where she formerly had breasts, leaving her feeling disfigured and questioning her womanhood.
"What is a woman without breasts?" wondered Leaphart. "I have always identified as a very feminine woman."
She thought she must have been given this struggle for a reason, but the reason was unclear until one day when she was vacationing at the beach with her daughters.
Leaphart chose to wear a T-shirt to the beach to cover up her scars, but she decided she didn't want to continue to hide the ugly truth about breast cancer and the impact it had on her body. She took off her top and stood tall on the crowded beach, showing bold scars where her breasts used to be.
"At first, people were shocked," says Leaphart. "A large group of people started to crowd around me, just staring. Then one woman started to cry. Then everyone started to cry and everyone burst into applause, congratulating me and thanking me."
She posted a photo of her bare chest on Facebook, and the photo immediately received over 100,000 likes. She was inundated with messages of support and gratitude from cancer survivors from all over the world. She then made it her mission to raise awareness about breast cancer.
This lead to her next big challenge: walking 1,000 miles across the country – topless. She began training, walking shirtless in Mississippi and Louisiana. She was on a practice walk in the Ninth Ward section of New Orleans when she met Brooklyn-based documentary filmmakers Emily MacKenzie (HBO's First Comes Love) and Sasha Solodukhina. They were instantly struck by her story and decided to film her journey. They made a promotional video and started a Kickstarter campaign to help fund the film.
In December 2015, Leaphart learned of a casting for another video being made locally. She took her 8-year-old daughter Madeline to audition for a role, but it was Leaphart who ended up with the part. After telling her story to the casting director, Beyoncé cast Leaphart in the Hope interlude and Freedom section of Lemonade. When the video debuted on HBO, Leaphart was thrilled.
"I had no idea it would be this powerful. It was beautiful. What Beyoncé made is important. It's strong. I'm strong. She's strong. Every woman in the video is strong. We are warriors."
Leaphart will begin her 1,000-mile bare-chested journey from Mississippi to Washington D.C. on Saturday, April 30. She plans to finish the walk by her 50th birthday on June 27.
A GoFundMe page has been set up to offset the costs of her upcoming walk. And she'll continue to share her journey on Facebook.