Authorities in Los Altos said City Councilman Terrence Cullinan, who killed himself with a shotgun blast after exchanging a few words with a sheriff's deputy, left a suicide note saying he couldn't cope with life anymore. San Mateo County Sheriff's Lt. Richard McKillip said Cullinan, 46, looked "nervous and agitated" when a deputy found him parked on a lonely road Tuesday night, and the councilman said he wanted to "turn his car around." Instead, McKillip said, Cullinan drove away and the deputy was trying to catch up when the window of Cullinan's car was blown out by a shotgun blast. He was dead at the scene and a note was found beside the body. "He was distraught over life," McKillip said. "His 18-year-old son (a computer genius who founded a successful software firm at 14) died last year of cancer and apparently he just couldn't face life anymore."