Neil Young has filed for divorce from Pegi Young, his wife of 36 years. The couple have performed together since the 1990s and collaborated to start the Bridge School, a non-profit school for children with severe physical and speech impairments.

Documents obtained by Rolling Stone show that Neil Young filed a petition for dissolution of marriage on July 29 in the couple’s home town of San Mateo, California. Pegi received a formal copy of the notice on July 31 and both have submitted a notice of alternative dispute resolution. A hearing is scheduled for December 12.

Neither Neil Young nor Pegi, a singer-songwriter, have commented publicly on the split, and the musicians’ representatives have not issued a comment. Some of Youngs’ biggest fans, at the blog Thrasher’s Wheat, offered only a tactful, poignant tribute: a selection of songs and videos that touched on the couple’s long relationship. These included unreleased songs such as Separate Ways, from 1975, and Love to Burn, from 1990, both of which speak of a strained marriage, and both of which Young performed at gigs this summer.

“I won’t apologise,” he sings on Separate Ways. “The light shone from in your eyes/It isn’t gone/It will soon come back again/Though we go our separate ways/Lookin’ for better days/Sharin’ our little boy,/Who grew from joy back then.”

Neil Young and Pegi met in 1972, when she was working as a waitress at a restaurant near his California ranch. They married in 1978 and have two children together, Ben and Amber. Ben, who is now in his 30s, was born with severe cerebral palsy; he now runs an organic egg business.

Speaking to Songfacts in 2010, Pegi said that the secret of her marriage to Neil was that they “enjoy each other”, “respect each other” and “admire each other”. “I’ve only been married to Neil Young, so I don’t know what it’s like to be married to anybody else,” she said. “He’s an interesting character ... we’re challenged by each other. We like to do things together, we hang out, we have fun together ... [but] a little space is always good. You can’t live in each other’s back pocket all the time.”

Pegi began singing backing vocals on Young’s tours in the 1990s, and last performed with him at the annual Bridge School benefit in October 2013. She has released three solo albums over the last decade and recently completed her own US tour. Although the couple were both announced as performers at the upcoming Farm Aid concert in Raleigh, North Carolina, Pegi’s name has since been removed from the official line-up.

Neil Young is reportedly back in the studio, working on a new album, as well as preparing the public debut of his Pono music player.