This Atlanta Journal-Constitution exclusive is the result of many phone calls over several days, building trust with the family of Joseph Griffin, who was murdered Monday in Afghanistan.

The pain had a precise beginning for the family of Joseph Griffin: the moment on Christmas Eve morning when government agents came to the door, bringing his wife, Rennae, the news dreaded by every wife of a man at war.

When the pain will ease, nobody can say, because it is compounded by the strangeness of his death and the lengthy process of unraveling why he died.

Griffin, a Newton County resident working as civilian adviser to the Afghan police, was shot and killed Monday at police headquarters in Kabul by a woman described as a police sergeant.

Questions have been swirling since: Who is the woman? Did she have permission to be there and carry a gun? What was her motive? Was the killing without either political overtones or personal connections, as authorities have said?

This week, the family struggled with their grief. They had a Christmas anyway at the family farm near Cedartown, if only to let the kids open gifts.

And they waited for the investigation to take its course.

“These days have been the longest of my life,” said Shay Griffin, the stepmother who raised Joseph. “His wife is so devastated.”

Rennae Griffin only managed to tell The Atlanta Journal-Constitution during an exclusive interview, “this is a very difficult time,” before she could say no more.

As the story played over and over on news sites and journalists called asking for a statement, Rennae struggled with how to put the enormity of her loss into words. “How do you sum that up in a statement?” she asked a family member.

This wasn’t how their lives were supposed to play out, she said. “This is not our story.”

Joseph knew the risks of his job, family members say, but they knew him too well to urge him toward safer employment.

“He would say, ‘This is my work,’” Shay Griffin said.

He believed he was serving the United States by helping the Afghan people handle their own security. A veteran of the U.S. Army and several Georgia law enforcement agencies, he had worked for DynCorp International advising security forces around the world since 2000.

He came to this assignment in Afghanistan in July of 2011. Reports that he was killed by a policewoman make it even harder for his family, which holds a special respect for police officers.

“He went there to help,” Shay Griffin said.

Joseph had noticed that Afghan children rarely smile, and he wanted to change that, said his brother-in-law, Brad Zutaut. So he took up a collection from his buddies and they helped build a playground for the kids.

“His need to help and make change was so great,” said Zutaut, 47, of Los Angeles.

Zataut and other family members are waiting at the farm, which was once owned by Joseph’s grandfather, to get his body back and plan his funeral.

“People have become numb to the names (of the dead) they see on TV,” said Zutaut. “I’ll never be numb again.”

Joseph’s son, Timothy, is coming from Frankfurt where he is a student. Father and son had recently taken a diving trip together in Thailand.

The woman detained in the shooting, Sgt. Nargas, walked into the heavily guarded compound in the heart of Kabul and killed him with one shot, officials said. (Like many Afghans, she has only one name.)

Afghan officials have offered contradictory accounts of whether she was authorized to carry a weapon at the site. Her motive remains a mystery. No militant group has claimed responsibility for the killing, which marked the 60th so-called “insider attack” this year.

At the time of the murder, Kevin Smith, who worked on his team in Afghanistan, was also inside the compound.

“I was in a meeting when they called me on my cell and told me something had happened,” Smith said. “I ran downstairs and there he was.”

Smith said the two men became close in the 17 months they worked there. They ate together, worked out together and drove to work together.

“When you are with someone during a battle or a war, you create a special bond — it goes beyond mere friendship,” he said. They called it “mission life.”

Smith, 46, will speak at memorial services for Griffin today in Afghanistan. He said he’ll tell people that Griffin was known as a “Grumpy old bear with a heart of pure gold.”

He’ll tell how Griffin once bought a plane ticket for a young soldier so he could see his critically ill mother.

When Griffin’s body arrives home, the Newton County Sheriff’s Department will provide an escort to the funeral home and for the service. Griffin worked two stints for that department some years ago.

“He mentored a lot of the deputies: tactical stuff, how to write a report, or how to do something better,” said Lt. Tyrone Oliver. “He was always willing to help.”

It was snowing Thursday in Kabul, and it was pretty cold as well in Georgia.

At the Griffin farm, Joseph’s uncle, Scott Bentley, recalled a diving trip the two of them took in Thailand. He was struck by how quickly Griffin came to know people, and how aware he was of his surroundings, if not on guard.

While they were in Thailand, Griffin’s barracks back in Kandahar were bombed, which upset him greatly.

Upset him, but didn’t deter him from going back to his chosen work.

“He was always on a mission to help people,” Shay Griffin said. “He traveled the world with that mission.”