Back from Iraq, Army Sgt. Kristofer Goldsmith remembers choking someone into unconsciousness at a party for no reason. "That's not who I was before I deployed," he says. His breaking point came when his unit was ordered to stay beyond their volunteer commitments. "I took my half bottle of Percocet and ... drank until I couldn't drink anymore." He survived and now lives with his parents. He's among the nearly 20 percent of returning U.S. veterans who suffer from post traumatic stress disorder or major depressionFull story at CNN.