They survived hell — and are determined to make something good come from it.

Former Oct. 7 hostage Keith Siegel is among those who have turned unimaginable trauma into a new sense of purpose — experiencing what psychologists call “post-traumatic growth” after 484 days in captivity.

After his February 2025 release, the American-Israeli threw himself into the campaign to free the hostages still in Gaza — meeting repeatedly with President Trump and other senior administration officials and speaking to audiences around the world.

“I did something I had never done before, and I never thought I would ever do, and I never believed I could do it,” Siegel, 66, told The Post.

“Something horrible happened to me, and because of that, people will listen to me,” he said. “So I have a voice.”

Three years after Hamas terrorists stormed into Israel, killing some 1,200 people and dragging 251 others into Gaza, many of the hostages who made it home have transformed the darkest chapter of their lives into a mission to bring light to others.

They have become artists and authors, advocates and humanitarians. Some have taken their unexpected platforms into business and technology, determined not simply to heal, but to use their trauma for good. 

Former hostage Eli Sharabi turned his 491 days in captivity — and the devastating loss of his wife and two daughters — into “Hostage,” which became the fastest-selling book in Israeli history and later a New York Times bestseller.

And Noa Argamani, whose terrified face became one of the defining images of Oct. 7 as she was hauled into Gaza on the back of a motorcycle, has embarked on a new career in venture capital.

Argamani, 28, who was rescued after 246 days in captivity, recently joined Vine Ventures, where the former artificial-intelligence student hopes to use the extraordinary international network she built while advocating for the hostages to help Israeli startups break into the US market.

“I lost a lot of people. I saw in my own eyes hell, being in tunnels, looking in Hamas’ eyes,” Argamani told Business Insider.

“But I choose every day to have another part of my life, to look forward, to go to work, and not let the grief become my identity.”

To be sure, not all survivors of the Oct. 7, 2023 terror attack have thrived — and many have spoken openly about their struggles after surviving the ordeal.

Shirel Golan, 22, who lived through the Nova Festival massacre, killed herself about a year after the attack. Her family blamed the horror of that day on her deteriorating mental health.

A 2024 report by the Knesset found that more than half of the 3,000 survivors of the Oct. 7 attacks had been referred for mental health counseling.

But survivors who spoke to The Post said they are striving to look forward like Argamani — and not let the violence of Oct. 7 overtake their lives.

Siegel and his wife Aviva, who was released after 51 days in captivity, turned that voice toward people far beyond Israel after the hostage campaign ended.

The couple traveled in January with Israeli humanitarian organization IsraAID to Kenya’s Kakuma refugee camp, where more than 300,000 refugees live after fleeing conflicts across Africa.

Keith said he was stunned by the parallels between their lives and his own experience in Gaza — hunger, thirst, poor hygiene, separation from family and the constant sense that death could come at any moment.

Afterward, the Siegels traveled across the US seeking support for IsraAID’s work.

“I just found that by doing that, and by learning to do things that I never thought I could do, and getting more self-confidence in doing that … I kind of felt like I’m growing as a person,” Keith said.

The couple also works with 255, an NGO supporting released hostages and their families.

For Aviva, 64, that mission has included putting her own experience into words.

Her book, “The Main Thing is to Wake Up to a New Morning,” recounts her captivity, her agonizing wait for Keith and the campaign that consumed her life until he came home.

“I feel like I’ve gotten out the words that I want to say,” she told The Post. “We were there. We went through what we went through, and we have to spread the truth.”

Andrey Kozlov, meanwhile, has found his outlet on canvas.

Kozlov, who was rescued alongside Argamani and two other hostages in a daring Israeli operation in June 2024, began painting his captivity after his release, building a collection he hopes to exhibit in New York.

Now he is racing to complete the larger body of work documenting Oct. 7 and captivity while the story remains fresh in the world’s consciousness.

“We all lost time. Some people lost a lot more than just time — members of families, homes,” Kozlov, 31, told The Post.

“We lost something and we can’t take it back, but we can make lemons into lemonade,” he said. “It’s part of the healing.”

Kozlov said he feels an obligation to create the paintings now — both for himself and as a record that might endure long after the headlines disappear.

“What is more important is what you do after,” he said.

“My task is just to express it, to paint and to make as much good as I can … to bring some light to the world.”

If you are struggling with suicidal thoughts or are experiencing a mental health crisis and live in New York City, you can call 1-888-NYC-WELL for free and confidential crisis counseling. If you live outside the five boroughs, you can dial the 24/7 National Suicide Prevention hotline at 988 or go to SuicidePreventionLifeline.org.