I read that one of Ellington's players in the 1940s left the band and slept for a year! I know it's an exaggeration, but still. I am tired after a week on the road, I can't imagine 3 years!
When Lawrence Brown got close to 65, he retired from the Ellington band (around 1970 or '71, I believe), went home, put his trombone behind his sofa, and apparently never played it again.
Lawrence Brown's very lengthy period of employment with Ellington no doubt put him in the position financially to do that:
http://en.wikipedia.org/wiki/Lawrence_Brown_(musician)
When I saw Shorty Rogers with the British National Youth Jazz Orchestra in 1982, it was said that he'd been persuaded to come out of retirement spent largely on his yacht in California. His Wikipedia entry suggests that music commissions, other than jazz, had been continuing:
http://en.wikipedia.org/wiki/Shorty_Rogers