The singer/actor, who plays MCKinley High graduate Finn on the musical Tv show, voluntarily enrolled in a treatment program to address "substance addiction" issues.
He took to his Twitter.com page on Friday (26Apr13) to express his gratitude to his well wishers, writing, "Sending out big love to everyone. Thank you for the continued support! It means the world to me!"
Monteith's girlfriend and Glee co-star Lea Michele also tweeted, "Today is a great day... Love you all!"
The actor was photographed reuniting with Michele at Los Angeles International Airport, where the couple was reportedly preparing to fly out of town.