- The gunman told an 18-year-old he won't kill him if he gives police an envelope
- But the teen was also forced to watch his classmates and teacher get killed
(CNN)The killer called him "the lucky one."
For reasons he might never understand, Matthew was chosen to live by the gunman in last week's Oregon community college shooting that left nine people dead.
But the 18-year-old had to perform two tasks to save his life: deliver the gunman's message to police, and watch his classmates get shot right in front of him.
The trauma, Matthew's mother said, has been overwhelming.
"He's different," Summer Smith said. "He'll never feel the same. He'll never feel complete security again."
She asked that Matthew's last name, which is different from her own, not be publicized.
The gunman, Christopher Harper-Mercer, barged into Matthew's classroom at Umpqua Community College on Thursday. Mercer shot three people, including professor Larry Levine. Then, he paused and turned to Matthew.
" 'You -- with the glasses -- stand up,' " Matthew recalled him saying, according to his mother.
"That's when the shooter gave him what he was told to give to police," Smith said.
The gunman handed Matthew an envelope containing a flash drive. Law enforcement officials said the flash drive contained the shooter's writings, which detailed his frustrations in life.
After Matthew took the envelope, he was told to sit in the back of the room and watch as Mercer resumed killing his classmates, his mother said.
The carnage Matthew was forced to witness was devastating.
"He doesn't know how to deal with it right now," the mother said. "I don't think he can register what happened yet. It's just too much."
Smith said she has no idea why the shooter locked eyes with her son and chose to spare him.
"I can't ask why anymore. I just have to be happy that Matthew is OK."
But his lack of physical wounds don't reflect the emotional turmoil Matthew will likely grapple with for the rest of his life.
"He lived," Matthew's mother said. "And for that, he feels guilty."