Why Adam gontier leave three days grace?

Adam Gontier left Three Days Grace in January 2013 to focus on his health and personal issues. He cited a struggle with addiction and the need for a break from the pressures of the music industry as significant factors in his decision. Gontier's departure marked the end of an era for the band, as he was the lead vocalist and a key songwriter for their earlier hits. He was replaced by Matt Walst, who has since continued with the band.