Blind marathon runner and his sighted trainer fall in love, prepare to race the New York City Marathon together

Jessie Rix was simply looking for a running buddy when she signed up to volunteer as a guide for disabled runners.

Instead, Rix, an avid runner, fell in love.

Rix, 28, was assigned to Anthony Butler, who lost his vision 10 years ago when he was the victim of a shooting.

“Everyone used to call me bright eyes so I’m like, ‘Oh my God, I don’t have my eyes anymore,’” Butler, 30, told “Good Morning America.” “That’s like my trademark. What am I going to do?”

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Butler turned to running as an outlet. He was matched with Rix by Achilles International, a non-profit organization that partners able-bodied volunteers with disabled runners.

Butler and Rix became fast friends as they learned how to keep pace with each other while attached to the tether they use to stay connected on runs.

For Rix, there was an immediate connection.

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“That first day I met Anthony, I was like, ‘I need that person in my life one way or another,’” she said. “He’s the happiest, most optimistic person in the world, and you just don't get that anymore.”

Over the past two years, Rix and Butler have completed four marathons together around the world.

This Sunday, they will run the New York City Marathon in their hometown.

“I never thought in a million years it would bring me here,” Rix said, speaking to Butler, of their love story. “I was just going out for a run and so were you.”