PARKLAND, Fla. — Kelly Plaur is still having nightmares almost every night. In the mornings, she recounts them to her mother, though the theme is usually the same: the horror she witnessed at Marjory Stoneman Douglas High School last year when a gunman opened fire in her classroom, killing two students and injuring four others.
A few weeks ago, Ms. Plaur, 18, had to withdraw from the paramedic training program she had started after she was overcome with anxiety while transporting a gunshot victim. Even the sight of certain window blinds can put her on edge, reminding her of the bullet holes that pierced the classroom blinds on the day of the rampage.
“Little things trigger me that I wouldn’t think would trigger me,” she said.
For young people like Ms. Plaur, more than a year after the school massacre in Parkland, Fla., that killed a total of 17 people, life remains fraught with traumatic memories, an enduring byproduct of the nation’s epidemic of gun violence. For many, the worries emerged again last week when two teenagers who attended Stoneman Douglas took their own lives within a few days of each other. Then, on Monday, the father of a little girl killed in the 2012 shooting in Newtown, Conn., also died in what authorities ruled was a suicide.
Experts warn that the motivations behind suicide are complex, and the recent deaths remain under investigation. But the three highly publicized losses over 10 days in two towns defined by tragedy laid bare the painful emotional injuries that can persist long after the gunfire has stopped.
Years later, many survivors of mass killings say they continue to struggle. Loud noises make them jumpy. The popping sounds come back in dreams. Talking about gun violence can lead to sudden back spasms.
They face these flashbacks, by and large, alone. In the immediate wake of the attacks, schools and communities come together and offer comfort, counseling and therapy. Students feel a cocoon of empathy from fellow students and teachers. Everyone asks if they are O.K.
Then time passes.
Hollan Holm was 14 when on Dec. 1, 1997, a fellow student opened fire at a prayer circle at Heath High School in West Paducah, Ky. Three students died and five others, including Mr. Holm, were injured. The bullet scraped his skull but did not penetrate it. He developed extreme sensitivity to certain sounds, like firecrackers and balloons popping. But he did not accept counseling, convinced he should just get on with his life.
Now 36, Mr. Holm still avoids sitting with his back to the entrance of a room. At church, he said, he is “hyper-aware” of people he does not recognize. When he enters any space, he tends to conduct a threat assessment of his surroundings. Last year, 21 years after the shooting, he went for several months to a trauma specialist.
“You can’t let the shooting define your whole life,” he said. “But you can’t put it behind you.”
Each person handles trauma differently. Factors such as age, proximity to the gunman, or whether or not someone suffered injuries or saw someone get shot influence the ability to rebound.
“The immediate acute response may resolve over time; the symptoms may decline,” said Rochelle F. Hanson, a psychologist who specializes in trauma treatment at the Medical University of South Carolina.
“What we worry about is people three or four months out who are still experiencing trauma-related symptoms. Those raise red flags,” said Dr. Hanson, who is also a director of training at the National Mass Violence and Victimization Resource Center.
School shootings can affect hundreds or thousands of people at once, including students, teachers, parents and emergency personnel. In Parkland, Stoneman Douglas alone has more than 3,000 students.
“It is difficult, getting out of bed and going back to school every day,” said Alex Wind, 18, a senior. The freshman building where the shooting took place still stands, fenced off, on campus. “It’s so hard walking by it every day.”
Right after a tragedy, schools flood campuses with counselors, therapy dogs and activities to help children cope. But if victims are in shock, it might be too soon to process what they have been through. By the time the shock wears off, services might no longer be as readily available.
“It’s kind of like a hurricane: Everyone wants to help as soon as it happens,” said Sarah Franco, the executive director of a South Florida charity running a new health and wellness center in Parkland. “Now, a year later, we have to take a step back and look at how we are doing. Are people accessing all of these services? And the answer is no, they’re not.”
The apparent suicides of Sydney Aiello, a 19-year-old Stoneman Douglas graduate, and Calvin Desir, a 16-year-old sophomore, prompted local leaders to rush to open the new center, which is funded by a Department of Justice grant and had been scheduled to begin its work in about a month. Similar programs were put into place after the school shootings in Columbine, Colo., and in Newtown, where Jeremy Richman, 49, who lost his 6-year-old daughter, Avielle, in 2012, was found dead on Monday.
On Monday, the Parkland center opened at a strip mall near Stoneman Douglas. Fliers stacked at the front door urged parents to ask their children if they had thought of suicide and especially whether they had gone as far as planning how they might kill themselves, a sign of high risk.
“We wanted to know if I could get therapy or something to help me,” one girl asked, her mother in tow.
Seeking help can be a difficult step for survivors to take. Lisa Hamp, now 32, was in a computer class her junior year at Virginia Tech when a gunman burst into the building. Afterward, as she was safely escorted outside, “I saw everything, dead bodies,” she recalled.
Having emerged physically unscathed from a shooting that left 32 people on campus dead, Ms. Hamp felt that she did not need to take up mental health counselors’ time. She built a hierarchy in her mind of those who deserved help: People who had lost loved ones were at the top, followed by the wounded.
“We put ourselves, the physically uninjured survivors, at the bottom,” she said. “We think we should just suck it up and move on.”
But she never quite managed to move on.
Ms. Hamp graduated with a degree in mathematics and went on to obtain master’s degrees in operations research and applied economics. Privately, she suffered from severe anxiety. “I was constantly prepared for the second shooting in my life. What if an intruder broke through the window?”
She channeled her stress into an obsession with exercise and weight, which eventually led her to develop an eating disorder. It took several years before she sought psychological counseling, which she said helped.
“Unfortunately, the most traumatized people, I don’t think we’ll ever see,” said Janelle Perritte, a licensed clinical social worker and Stoneman Douglas alumna. “They work to try to isolate themselves.”
As a 17-year-old junior at Columbine at the time of the 1999 shooting, Andy McDonald remembers going to a counseling session and concluding that therapy was not for him. Instead, he kept a journal, he said.
“I was really fortunate to get connected with different people in the aftermath, where I could go around and kind of share my story to different schools and different places around the country,” said Mr. McDonald, now a 37-year-old middle school teacher in New Hampshire. “Being able to talk about it, for me, was extremely helpful.”
He still struggles when other shootings happen, or when major Columbine anniversaries near. It will be 20 years on April 20. “There’s not a day goes by that I don’t think about it in some capacity,” he said.
Randee Gregory was a third grader on Sept. 26, 1998, when a young man entered Oakland Elementary School in Greenwood, S.C., and began shooting. Though a girl sitting across from her died in the shooting, Ms. Gregory, now 39, cannot recall the gunfire.
“I remember being pushed out the door and running down the hall. But I blocked out the shooting part,” she said. “I assume it is a survival mechanism.”
Everyone soon returned to school. There was no counseling of any kind — which Ms. Gregory does not hold against anyone. “School shootings were not a regular occurrence back then,” she said.
To this day, Ms. Gregory, who works as a state tax auditor, tries to sit facing the exit. Sometimes, she still dreams that someone is chasing her and trying to shoot her. Her 5-year-old daughter, Rylee, is starting school next fall.
“It terrifies the death out of me,” Ms. Gregory said. “I am not sure that schools are any safer now.”
Neither is Jordan Gomes, 15, who was 9 and in fourth grade at Sandy Hook when a young man killed 20 children and six adults on Dec. 14, 2012.
“Nothing can fix what that day broke inside of me and in every child in that school,” she said. “My biggest fear walking into school every day is not the homework or the tests. It is the fear that I will not live to leave at the end of the day, or that if I do, my friends will not. I cannot bear the thought of burying my friends.”
Ms. Plaur, the young woman who recently left her paramedic training, said a counselor at Stoneman Douglas told her shortly after the shooting that she would have to “get over it.” It felt dismissive, she said, and it contributed to her decision to finish high school at another school.
Soon, Ms. Plaur thinks, she might want to try therapy.
“I’m ready now,” she said.