Cory Monteith's Not Alone: Demi Lovato, Ben Affleck and More Stars Who've Entered Rehab

From Ben Affleck to Charlie Sheen, see the celebrities who have received help for their addictions

Cory Monteith isn't the first celebrity to seek treatment in the public eye.

The Glee star, who entered rehab over the weekend for problems with substance abuse, joins the long list of Hollywood stars who've battled addiction.

From singers like Demi Lovato and Britney Spears to actors Ben Affleck and Robert Downey Jr., see the many celebs who've battled personal demons and decided to seek help in hopes of living a healthier lifestyle.