Heaven (2008)

Two mental patients bond in an imaginary heaven where nothing bad can ever happen, only to realize that being cured of their condition would mean accepting the harsh realities of life. He lives in a mental hospital, but escapes to his own private heaven to spend his days with his dead mother. She was a deeply disturbed woman who turned her back on reality following a traumatic experience. When they meet in heaven, they are happy. Now, a doctor has appeared in heaven claiming to possess the cure that could restore normalcy to their lives. But what's normal about a world with so much pain, and why would they ever want to return to a world with nothing to offer them but heartache and misery?

Unfortunately the movie Heaven is not yet available on HBO Max.