By Christopher Rosen
Updated May 13, 2015 at 01:17 PM EDT
Credit: Kevin Winter/Getty Images

Last year, Stapp made headlines for his erratic behavior. The singer claimed he was the victim of severe financial fraud and also left a message at his son’s school about an imminent ISIS attack there.

Stapp told PEOPLE that he had a “psychotic break” brought about by alcohol and drug abuse. (At the time, Stapp’s wife, Jaclyn Stapp, tried to get Stapp put on a psychiatric hold and said he was under the influence of drugs.)

“In my delusional thinking, I thought my family was involved in ISIS, and that millions of dollars had been taken from me to support terrorism,” Stapp said. “All of it was nonsense. I was out of my mind.”

Stapp has since gone into recovery, and has received treatment for his addiction and bipolar disorder. “Nothing is more important than my sobriety,” he told PEOPLE.

For the full interview with Stapp and his wife, head to PEOPLE.