John Mayer is moving on from Jennifer Aniston in the only way a musician knows how -- through a song.

According to US Weekly, Shadow Days, off his new album Born and Raised, is his final farewell to his famous ex.

Listen to Shadow Days here

"Shadow Days is about Jen," says a source. "It really took him a long time to get over her. He really loved her a lot."

"He wrote the song as a farewell letter knowing [Jen] would hear it. Ultimately he's done a lot of self reflection though and it he realizes they weren't right for each other."

The couple first got together in April of 2008 and after numerous breakups, they officially called it quits in 2009.