Peter Linnerooth was an affable, punctual and conscientious graduate student at Minnesota State Mankato. He later earned a doctorate degree, became an Army psychologist and was deployed to Iraq during the height of the war. When he returned to Mankato, Linnerooth was a paranoid and disorganized assistant professor, friends say.

He went to Iraq to help U.S. troops deal with the damage post-traumatic stress disorder inflicts, but upon return, he also was in the clutches of PTSD, said his mentor Dan Houlihan, professor director of Minnesota State’s School Psychology Doctoral Program.

On Jan. 2, Linnerooth, 42, killed himself in Mankato.

Linnerooth was awarded a Bronze Star after an honorable discharge in 2008 and became critical of the military’s limited work on providing mental health care to soldiers, particularly to those with PTSD, in the pages of Time magazine and the New York Times. Capt. Linnerooth will be buried with full military honors at 11 a.m. Monday, Jan. 14, at Fort Snelling National Cemetery.

“He was really, really suffering,” Linnerooth’s widow, Melanie Walsh, told Time for its story on his death. “And it didn’t matter that he was a mental health professional, and it didn’t matter that I was a mental health professional. I couldn’t help him, and he couldn’t help himself.”

Houlihan was Linnerooth’s adviser as he earned his graduate degree and later sought to hire Linnerooth after his military service, which began in 2002. Linnerooth was an assistant professor at Minnesota State Mankato for about 18 months in 2008 and 2009, where he concentrated on “clinical interpersonal dynamics,” according to his school biography.

“When he went in and when he came out, it was shockingly different,” Houlihan said of Linnerooth’s military service. “He had very clear symptoms of PTSD.”

Houlihan and Linnerooth shared an office wall in Mankato, and Houlihan knew Linnerooth was in his office whenever he heard the motor of his paper shredder.

After Mankato, Linnerooth continued his work on the mental health of soldiers and returning veterans, especially those suffering from PTSD, with Veterans Administration medical centers in Capitola, Calif., and Reno, Nev.

His writing appeared in the medical journal of the American Psychological Association.

“That was the most vivid thing that stood out: He was a brilliant writer,” Houlihan said. “He was the best pure writer I’ve ever dealt with. He had a writer’s flair.”

After his career as an Army psychologist, Linnerooth was critical of the Army and its response to the mental health needs of soldiers. In a 2010 interview, he lambasted military leadership for not being more connected with on-the-ground troops and for not allocating more resources for mental health programs, Time said.

“The Army has been criminally negligent.” Linnerooth said.

In a 2009 New York Times article, Linnerooth said during his deployment in Germany, he was the sole psychologist for a community of 10,000 people in 2005. In the article, Linnerooth told a story about how he had treated a burly man whose job in Iraq was to recover the bodies of soldiers, and how one instance particularly haunted the soldier.

“He had picked up this corpse that was so badly burned, it weighed about 20 pounds,” Linnerooth said. “He was this big, tough, awesome guy. For him, it was like picking up his daughter. That was an extreme case. But you get those at least once or twice a week.”

Larry Shellito, commissioner of Veterans Affairs for Minnesota, didn’t know Linnerooth but talked about the reach and grip of PTSD.

“Oftentimes, you have to look at the people that surround the people with (PTSD) to make sure they are also OK, because it’s got a multiple impact,” Shellito said. “It’s not just the individual who suffers, it’s the people who care for him.”

Retired psychology professor Wayne Harris got to know Linnerooth when he worked as Harris’ graduate assistant.

He recalls Linnerooth as bright, witty and “very conscientious.”

“Really, he was just the type of person you’d want to be helping people, but that takes a personal toll,” Harris said Saturday from his Minneapolis home. “He needed some support in his role, too.”

Linnerooth was a psychologist with the U.S. Army in San Antonio; Schweinfurt, Germany; and Iraq, where he was stationed for 18 months. His time in the Middle East, which spanned 2006 and 2007, was a period of escalating conflict and increased presence of U.S. service members called “the surge.” His Bronze Star was awarded for “meritorious service” in a combat zone.

“Having intellectual knowledge doesn’t protect you from the effects of seeing things … seeing people in difficulty, seeing people in pain, seeing people severely injured. Those memories are with you for a long time,” Harris said. “There is no immunity from that.”

He added that the effects of PTSD can strike long after the disorder’s onset.

“Those scars are still there, and if things start falling apart in your life, those scars are going to have an effect,” Harris said.

Houlihan said the scars came from being thrust into helping assist during surgeries after combat.

“If they had wounded people, he would scrub up and be in there,” Houlihan said. “There is no training in psychology to prepare for that. And he saw things that he couldn’t reconcile.”

According to a friend quoted in Time, Linnerooth lost his job with the Veterans Affairs department in Reno when he missed a two-year deadline to get his state psychologist’s license.

“He would have periods where he could get into something (at work), but then he would slip back into it” — the effects of PTSD, Houlihan said. “It was a struggle.”

Linnerooth also had started struggling in his second marriage, Time said.

Houlihan said Linnerooth’s work should have focused on writing instead of working as a therapist.

“The military needs to be more up front to help people prepare, and Peter never lived to tell people that,” Houlihan said.

Linnerooth was born in Minneapolis, grew up in Mankato and attended high school in Rochester, according to his obituary. He obtained degrees from Concordia College in 1992, Minnesota State Mankato in 1995 and the University of Nevada, Reno in 2004.

Time said Linnerooth is survived by his wife, Melanie; his mother, Gayle McMullen; a sister; three children, including two from a previous marriage; and two stepchildren.