And she was with some of his associates outside the Lorraine Motel, walking to a diner to have some catfish, when she heard the gunshot that ended his life.
"I never took my eyes off of him. I'm watching him being lifted up and being thrown back," Ester recalled Wednesday, 50 years to the day after King was killed.
She doesn't remember quite how she got up to the balcony where his body lay. But moments later, there she was with the others, at his side.
"I knelt down and tried to get a pulse, and barely anything was beating," she said. "So, I unbuckled his belt ... trying to aid him in getting air.
"I indicated for someone to get towels out the linen hamper that was on the balcony. And then I removed myself so that Marrell (McCollough) could put the towel on his neck and try to slow down the bleeding process."
Ester told CNN's Erica Hill that every April 4 since then has been difficult to bear, in part because pictures from the assassination scene are re-circulated in the news media.
But it's more difficult to deal with now, she says, "primarily because we have circled back to where we may have been 50 years ago as far as what's just and right for God's people -- all of God's people, and not just a selected few."
"Economic inequality was an issue in 1968 with sanitation workers. Economic inequality is still an issue today," she said. "Criminalization of people of color; maternal health care; our educational system. Here in the city where I live, we have a predominantly African-American high school now.
"So, I ask myself often: Where do we go from here? It has to be through love, building relationships with other people, and trying to make a difference. And speaking out. We have to start speaking out."