In war, there are two fronts - one where troops face the enemy in battle. And one where their loved ones wait, and worry that they'll receive the worst kind of news.
On May 11 - a roadside bomb killed Marine Sergeant Kenneth May and Corporal Jeffrey Johnson in Garmsir, southern Afghanistan.
Half a day later and halfway around the world in Southern California, May's wife Krystal got a knock on the door.
"I looked through the peephole and saw the Marine," she said, "and immediately I knew that my husband was dead."
Kenneth May was 26 years old. He and Krystal had been high school sweethearts in Kilgore, Texas. They were married two years to the day when he was killed.
"This is his purple heart," she said, showing the medal off.
May was presented with presented with the Purple Heart, given to anyone wounded or killed in combat.
There are some 200,000 U.S. military personnel in Afghanistan and Iraq today. Each one has a family waiting back home, anxious for good news - but fearful they too will get that knock on the door.
Nicole Morse is Krystal's best friend. Her husband Jim Morse is a sergeant in the same company as Kenneth May.
"It has been really tough - because while I am going through day-to-day things with her and helping her with what she has been going through - in the back of my mind is that my husband is still over there," Morse said.
We showed Nicole Morse some video we had shot of her husband the previous month in Afghanistan.
In the video, Sgt. Morse said, "they say that the deployment is harder on the spouse than it is on the Marine - and I completely agree. I have to deal with the physical threats here, but that can't be as bad as just not knowing."
"I am not sure what to think about that other than that I am totally flattered that he respects what we do," Nicole said.
What the military spouses do back here is wait, pray - and try to live normal lives amidst other people who have no idea what they are going through.
"There really is no 'Military wife 101,'" Nicole said.
Nicole can't wait for her husband to come home in November at the end of the deployment. For Krystal, there will be no homecoming.
"We talked about this as a very likelihood - as a very likely possibility that it might happen," Krystal said. "Did I want my husband going to war? No. But that was his choice."
Each one of the Marines is a volunteer, and they know what they are getting in to. For the families back home, dealing with what they don't know is often the hardest battle.
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