A prominent Manhattan emergency room doctor who had treated a staggering number of coronavirus patients killed herself in Virginia, authorities said Monday.

Dr. Lorna Breen, 49, the medical director of NewYork-Presbyterian Allen Hospital’s emergency department, died by suicide in Charlottesville, a spokesman for the local police department told the Daily News.

Spokesman Tyler Hawn said police responded to a call Sunday seeking medical help, and Breen was rushed to UVA Health System University Hospital but succumbed to self-inflicted injuries.

“She gave what she had, and she’s a casualty of the war in the trenches, as far as I’m concerned,” her father, Dr. Philip Breen, told The News. “She’s a true hero.”

Breen’s father said the crush of coronavirus cases his daughter handled was overwhelming, and that she herself became ill with COVID-19, though she went back to work after a week and a half. She had no history of depression, he said.

“She was a very outgoing, very energetic person who, I don’t know what snapped, but something blew up in her, and so she ended up taking her own life,” he said. “She just ran out of emotional gas.”

He said his daughter traveled to Charlottesville to stay with her sister after the hospital sent her home a second time.

“She stayed home about a week and a half, but I think she felt guilty about not being at work,” her father said. “The last time I talked to her was before she went in for her 12-hour shift that she couldn’t finish.”

“Just before she went back, she said that the ambulance had been waiting outside the building for over three hours with sick people. They couldn’t even get the people out of the ambulances in there,” he added.

On Monday, Columbia University Irving Medical Center and New York-Presbyterian hailed her tireless devotion to her work.

“Dr. Breen is a hero who brought the highest ideals of medicine to the challenging front lines of the emergency department,” the statement said. “Words cannot convey the sense of loss we feel today.”

The statement added the hospital would focus on providing “support to her family, friends, and colleagues as they cope with this news during what is already an extraordinarily difficult time.”

The Charlottesville Police Department also extended its condolences.

“Personal Protective Equipment (PPE) can reduce the likelihood of being infected, but what they cannot protect heroes like Dr. Lorna Breen or our first responders against is the emotional and mental devastation caused by this disease,” Charlottesville Police Chief RaShall Brackney said.

Breen, a devout Christian who was one of four siblings, traveled the world to give lectures on emergency medicine, and to hike and snowboard, her grieving father recalled.