"Nobody understands how it feels to be in a room and literally feel, 'These are the last moments of life,'" Eden Hebron says

It has been more than a year since the February 14, 2018 mass shooting at Parkland, Fla.’s Marjory Stoneman Douglas High School claimed the lives of 17 students and staff members. But the emotional fallout hasn’t ended.

Recently, two students — 16-year-old Parkland sophomore Calvin Desir and 2018 graduate Sydney Aiello, 19 — have died by suicide, as did Jeremy Richman, whose 6-year-old daughter Avielle was among the 26 people murdered at Sandy Hook Elementary School in 2012.

To honor the memories of those lost and help raise awareness of the mental health issues that can linger after gun violence, PEOPLE spoke with six Parkland students about their experiences then and now.

When a gunman opened fire inside her Parkland, Florida, school and killed 17 people, Eden Hebron hid under a table and watched in horror as her friends were murdered in front of her.

The terror remains vivid. “I don’t think I’ll ever be able to forget what I saw in that classroom,” the 16-year-old says, adding that she flinches every time she hears a loud noise.

“You can try to imagine, you can try to sympathize … but nobody understands how it feels to be in a room and literally feel, ‘These are the last moments of life,’” she says.

Eden Herbron
| Credit: Jeff Vespa/@portraits

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Therapy has enabled her to process her memories of those moments, which don’t dominate her thoughts as much as they used to. Still, she believes that for other survivors, therapy carries a stigma, which prevents them from getting the help they need.

“Some families still consider it, like, ‘Oh, it’s a shrink. Are you going to talk your feelings out?’” she says.

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In response, Hebron, who aspires to a career in technology, has developed an app that matches a person’s symptoms of stress, anxiety and depression with ways to address those problems. She hopes the app will help students all across the country.

“So many kids have anxiety. This shooting impacted people all over the country,” she says. “This app is a way to give them the tools to help themselves.”

If you or someone you know is considering suicide, please contact the National Suicide Prevention Lifeline at 1-800-273-TALK (8255), text “home” to the Crisis Text Line at 741-741 or go to suicidepreventionlifeline.org.