Mike Campbellis ready to shed some light on his complicated friendship with the lateTom Petty.

But he also witnessed the darker periods in Petty’s life, and felt too powerless to intervene.

“We’re dudes.”

Los Angeles - CIRCA 1987: Music legends Tom Petty and the Heartbreakers pose for a portrait in Hollywood, California

Tom Petty and the Heartbreakers in 1987.Aaron Rapoport/Corbis/Getty

That method of communication went beyond the music.

Aaron Rapoport/Corbis/Getty

“It would have gone like this,” he explained.

“‘Tom, I’m worried about you.

IRVINE, CA - OCTOBER 02: Guitarist Mike Campbell (L) and Musician Tom Petty perform at Verizon Wireless Amphitheater on October 2, 2010 in Irvine, California.

Michael Schwartz/WireImage

You’re hurting yourself.

Maybe you ought to think about cleaning up.’

It’s my business.

Mike Campbell and Tom Petty perform onstage at What Stage during day 4 of the 2013 Bonnaroo Music & Arts Festival on June 16, 2013 in Manchester, Tennessee. (

Mike Campbell and Tom Petty perform in 2013.Jeff Kravitz/FilmMagic

Leave me alone.'”

Added the guitarist, “You couldn’t talk Tom into anything.”

If you need me, call me.'"

His death came days after the iconic rocker completeda massive 40th-anniversary tourwith his bandmates.

Jeff Kravitz/FilmMagic

He added, “There was no second thoughts or reservations about going out on tour.

Are you up to it?'

He said, ‘I’m not staying home.

I’m going out.

I want to do it.

If I have to be in a wheelchair, I’m going to do it.'”

“Tom said, ‘I need to be out there.

I want to play with the band, and we’re going to do it.

I’ll be okay.’

So I have no second thoughts about it.

I don’t beat myself up like that.

I did all I could.”

The book hits shelves on March 18.