Experts say people like Capt. Sullenberger and others who survive tragedies can have a difficult time coping.

Imagine, if you will, saving the lives of 159 people.

It must be a great feeling, knowing that your actions had a profound effect on so many.

The movie “Sully,” which comes out today, takes a deep dive into the experience of one such person. Capt. Chesley “Sully” Sullenberger.

Director Clint Eastwood offers his take on what happened to the pilot, after he successfully landed a U.S. Airways jet on the Hudson River in New York in 2009.

Just minutes after takeoff, the plane’s engines sucked in a flock of geese and the aircraft engines died. But because of his training and experience, Sullenberger landed the plane on the river, saving the lives of everyone on board.

A new American hero was born.

But Sullenberger was never comfortable being called a hero. In an interview on “60 Minutes” later that same year he spoke about how he struggled emotionally in the aftermath of the crash, questioning what more he could have done differently.

“I still feel a responsibility for everything that happened. That’s literally part of the job,” he said.

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People who survive trauma — a plane crash, a natural disaster, a mass shooting, or a cancer diagnosis — experience a litany of emotions in the aftermath.

Stress, fear, and anxiety are fairly common.

But the feeling that Sullenberger alluded to, “hero’s guilt” or “survivor’s guilt,” is also very real, experts say.

The American Psychiatric Association (APA) includes it as a common reaction of mass shooting survivors. The U.S. Department of Veterans Affairs also calls it a common reaction after trauma.

“I think part of survivor’s guilt is a natural response to grief,” Tanis Taylor, L.M.F.T., told Healthline. She is a counselor at the Cancer Treatment Centers of America, in Tulsa, Oklahoma. “Some of it’s subjective, and some of it’s objective.”

Rita Helfrich is far too familiar with the feeling of survivor’s guilt.

In 2012, she was diagnosed with stage 1 breast cancer and underwent a double mastectomy. In 2015, the cancer came back but at stage 4.

This time Helfrich decided to seek treatment at the Cancer Treatment Centers of America. For months she traveled six hours by car, roughly every three weeks from her home in Illinois to the center in Tulsa, Oklahoma.

Each treatment visit lasted two to three days.

During her time there, Helfrich made many friends. The patients usually bond quickly, she said, and when one of them doesn’t make it, it’s devastating.

She mentions a woman named Rose she met early on. They both had a love for the St. Louis Cardinals. Last December when Helfrich came back to Tulsa, her friend was gone.

“When Rose passed away, I felt really guilty,” Helfrich told Healthline, taking a moment to compose herself. “You ask yourself ‘Why am I still here?’”

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This is the same question Pauline Harris found herself asking after witnessing the World Trade Center’s Twin Towers fall on 9/11. She lived two blocks from the buildings with her husband.

“I thought we were at war,” she told Healthline.

For months after, Harris constantly thought about everyone in the towers and questioned why she and her husband escaped injury and death.

“All those people,” she said. “I just felt horrible for them.”

“Sully” shows in great detail what it was like for Sullenberger to land the plane, and the aftermath, including an investigation into what went wrong. But Eastwood also takes time to show a man who is reeling from a traumatic event.

Sullenberger himself said on “60 Minutes” that the days immediately following the crash were “difficult,” “intense,” and “a blur.”

Many scenes in the movie capture his restlessness. In particular, the camera follows Sullenberger as he runs through the deserted streets of New York.

In a New York Times interview, location manager, Patrick Mignano, said those scenes were designed to depict the internal strife.

“It’s his isolation,” he said, “He’s in his head, and he’s second guessing himself.”

Second guessing is another way to describe survivor’s guilt, Taylor said.

“Our brains are wired to ask “Why?’” she said. “When bad stuff happens, if we can figure out the ‘why’ then we have control.”

Taylor said getting to the root cause of survivor’s guilt is crucial in the recovery process.

“Are there other feelings underneath that?” she said. “It’s important to recognize that loss and what it may trigger.”

Taylor uses art, dance, and music, plus many other therapeutic methods to help her patients work through survivor’s guilt. The overall theme is mindfulness.

Through guided meditation, imagery, and deep low breathing, people with survivor’s guilt — regardless of the cause — can amass the tools to help them through those time when they are “emotionally flooded,” she said. The idea is to retrain the thought process during those desperate moments.

“You can tell yourself, ‘I don’t need to do that anymore, I don’t need to run for my life,’” Taylor said.

Harris, who was also diagnosed with PTSD about four years ago, uses mindfulness to help keep the emotional wounds at bay.

“I put two feet on the ground and make myself feel present,” she said.

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Helfrich, who received a clean bill of health earlier this year, also uses a number of methods to guide her out of her darkest days.

But she attributes her faith as the number one reason for helping her beat back the cancer.

“I am spiritually engaged,” she said. “That’s a huge factor in my recovery process.”

Jim Whitaker also credits his “foundation of faith” in getting him through, not one, but two plane crashes.

The architect was on the U.S. Airways flight that Sullenberger piloted. He is depicted as the man in the movie who holds a baby as the plane goes down.

Years earlier he was on an 11-seat prop engine plan that caught fire and had to make an emergency landing.

That crash left him “stunned” he said. The U.S. Airways crash had a more profound effect.

“When I got back to Charlotte, I had sleepless nights for sure for a short period of time and an inability to focus,” Whitaker told Healthline.

The emotional toll that people face after a traumatic event, be it surviving a plane crash, watching the Twin Towers collapse, or beating back an aggressive form of breast cancer, can be overwhelming, Taylor said.

If someone is experiencing feelings of survivor’s guilt or any other emotional reaction that is making it difficult to live life, she added, it’s important to seek medical care.

“There is no shame in seeking professional help,” Taylor said.