tonight dave owens introduces us to sergeant dewitt osborne. >> we always talk about our friends that killed or us getting severely wounded, but we never talk about the guy that we killed. >> reporter: few can man dewitt osborne's mental -- imagine dewitt osborne's mental anguish. >> it haunts me every day. >> reporter: couple that with the physical injuries sustained in baghdad when a vehicle he was driving hit a roadside bomb. >> six titanium anchors in my right shoulder, a plate in my pirate foot and two prosthetic vertebrae -- right foot and two prosthetic vertebrae. >> reporter: it equaled pain and depression. >> i ballooned up to 218 pounds. >> reporter: because he couldn't exercise, something he says killed three of his friends who were trying to recover with him. >> something told me i needed to do something. >> reporter: a friend of his introduced him to golf. >> i never had a club in my hand. >> reporter: but he kept swinging and swinging and swinging. >> it gave me a sense of accomplishment. so i started to slowly come out of that dark depression. i had something in my hand