It’s been just over a month since Soundgarden’s Chris Cornell was found hanging in his hotel room after a performance. His sudden death was ruled a suicide, but his widow says something else is to blame.

Vicky Cornell gave her first interview since her husband’s passing to PEOPLE, and opened up about the factors that she feels actually led to his death.

She revealed that the night Chris died, he had turned lights in the family’s Los Angeles home on and off from his Detroit hotel room using an app, which seemed odd. When she called Chris, he was “ranting” and “mean” to her over the phone. She told the singer, “You need to tell me what you took.” She then called his bodyguard, Martin Kirsten, who confirmed Chris had doubled his dose of his anxiety medication, Ativan.

Vicky blames the Ativan for altering her husband’s mood and causing suicidal thoughts, which is a rare side effect of the drug. She said, “He didn’t want to die. If he was of sound mind, I know he wouldn’t have done this.”

Vicky said, “My Chris was happy, loving, caring and warm. This was not a depressed man—it wasn’t like I missed that. What I missed were the signs of addiction.” She added, “Addiction is a disease. That disease can take over you and has full power.”

The star’s widow also shared that her mission now is “to do everything in my power to make sure other children don’t have to cry like mine have cried.”