Brian Wilson is postponing his tour, citing mental health issues in a lengthy letter to fans posted on his website.

Admitting he feels “mentally insecure,” the former Beach Boy says he regrets the decision to postpone dates on his Pet Sounds and Greatest Hits tour, writing it’s “not good for me to be on the road right now.” His tour is scheduled to run through the fall with the Zombies as the opening act.

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“It is no secret that I have been living with mental illness for many decades,” reads the letter posted to his website. “There were times when it was unbearable, but with doctors and medications I have been able to live a wonderful, healthy and productive life with support from my family, friends and fans who have helped me through this journey.”

The musician, who suffers from schizoaffective disorder, has been public about his mental health struggles over the past 50 years.

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Wilson writes that though he is “physically stronger” following his third back surgery last year, he says he hasn’t felt like himself and is working with doctors to figure out what’s wrong.

“I had every intention to do these shows and was excited to get back to performing,” his letter reads, describing his feelings as “scary” and “strange.” “I’ve been in the studio recording and rehearsing with my band and have been feeling better. But then it crept back and I’ve been struggling with stuff in my head and saying things I don’t mean and I don’t know why. It’s something I’ve never dealt with before and we can’t quite figure it out just yet.”

“I’m going to rest, recover and work with my doctors on this,” he writes. Wilson says he hopes to be back on the road later this year and he thanks fans for their ongoing support.

“I’m looking forward to my recovery and seeing everyone later in the year. The music and my fans keep me going and I know this will be something I can AGAIN overcome,” the letter concludes.

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