Two days after 9/11, Jesus Medina volunteered for the Army.
He deployed to Iraq in 2005 and eventually found himself on an elite team of soldiers hunting "higher tier targets ... generals."
Medina spent a lot of time driving an armored vehicle. He recalls one of the two times he hit a roadside bomb.
"I'm turning right, and boom!" Medina said, gesturing with his hands. He said next came darkness, followed by screams. "And then, all of a sudden, Hell."
Some of his comrades were seriously wounded. During Medina's time in Iraq he saw a lot of people die -- both Iraqis and his fellow soldiers. Once, a close friend was shot in the neck.
But there weren't a lot of ways to cope with the daily violence.
"A lot of us had to do something so inhumane to be able to stay human. Which was ... shut off everything," Medina said, with tears in his eyes. "I was married at the time. I stopped calling my wife for almost two months."
A CONSEQUENCE OF WAR THAT'S 'CLEARLY BEING MISSED'
Researchers have amply documented veterans' PTSD and depression, but grief has not gotten the same level of attention, said Roxane Cohen Silver, a UC Irvine psychological science professor who co-authored a study of grief among veterans.
"What we're identifying are very important psychological consequences of serving in the war that are clearly being missed," she said.
"We think of soldiers as these warriors that don't have emotions, but we're dead wrong about that," said study co-author Pauline Lubens, who earned a doctorate in public health at UC Irvine last year.
Medina was one of the nearly 200 post-9/11 veterans who participated in the UC Irvine study.
It found that combat exposure is almost as likely to cause grief as it is to lead to post-traumatic stress disorder.
The researchers also found that post-9/11 veterans who lost fellow service members both to combat and suicide dealt with the losses differently, and that combat loss was easier to accept than suicide.
THE 'AHA' MOMENT
Lubens said she had an aha moment when an Army vet approached her after she spoke at a campus Veterans Day event a few years ago. He talked about friends who died in combat or by suicide.
"And while we were talking, I realized, I never hear anybody talk about grief or loss in people who served in combat," she said.
While Lubens conducted the study, one of the veterans said to her, "People are calling me a hero when they don't even know what I did over there. I mean, if I was such a hero, why did I lose so many guys?"
Only about half of 1 percent of the U.S. population serves in the military. Lubens said that contributes to isolation and detachment from the civilian world for many veterans.
"People actually come up to a veteran and ask them, 'Did you kill anybody?'" she said, "which is such a rude question. But it's a question I think based on not knowing what else to ask."
Instead of asking veterans whether they had killed anyone, Lubens said people should ask whether they had lost anyone.
'THERE REALLY IS NOTHING THAT CAN FIX THAT BURDEN'
Silver previously conducted a large study of Vietnam veterans a few decades after that war. She said it found that civilians did not want to hear about veterans' combat experiences, and that veterans felt most comfortable communicating with fellow vets.
"I think one of the messages of this [current] study is that not much has changed in that regard over the decades," she said.
So what's to be done? Lubens believes clinicians need to talk to their veteran clients about grief. And she said there's a need for more research to find effective ways to help troops deal with grief while they're in the service, and afterward.
Lubens, who is now with the Institute for Veteran Policy at Swords to Plowshares in San Francisco, said she plans to expand upon the grief study.
But Jesus Medina isn't optimistic anything will help. He said most veterans he knows are lonely and don't feel understood.
"No matter what, whether you understand grief or not, you have a relationship with it," he said, "and if you don't understand it, it really kills you and your family. And when you get to that point, there really is nothing that can fix that burden."
Since coming home, Medina said he's lost two fellow soldiers to suicide. He believes it's because they didn't know what to do with their grief.
This story was produced by the American Homefront Project, a public media collaboration that reports on American military life and veterans. Funding comes from the Corporation for Public Broadcasting.