BOSTON ( TheStreet) -- On April 6, 2009, 21-year-old Army Specialist Adam Kuligowski took his rifle into a bathroom stall at Bagram Air Base in Afghanistan and shot himself. His last words were found in a suicide note to his father, Michael Kuligowski: "Sorry to be a disappointment."Just weeks earlier, Adam had visited his dad in Thailand. Michael Kuligowski works as an information officer at the U.S. Embassy in Bangkok. During his 18-day visit, Adam had complained of sleeplessness. He had mentioned being late for work, and the push-ups he had to do as punishment. And he had talked about some extra guard duty. Michael Kuligowski is an Army veteran and saw all of that as standard-issue Army life. There had been problems the father didn't hear about. In the fall of 2008, Adam had been ordered to kitchen duty on his days off, after he threw his gun on the ground and told his commander to send him to jail. Michael Kuligowski later learned that his son had been suffering from depression. Sleeplessness at night had left Adam exhausted during the day, when he needed to be sharp. Adam was attached to the 101st Airborne's Special Troops Battalion, tracking enemy communications as a signals-intelligence analyst. In a report about Adam's last disciplinary meeting, a commanding officer noted that the young soldier was falling asleep in front of him. The same report showed a photo of an overturned footlocker in Adam's quarters. It noted that Adam was awake at all hours, playing online video games.