The New Order frontman was close pals with Curtis when the group was still called Joy Division, and he was desperate to save his friend from the pit of despair.
He spent two weeks with Curtis prior to his suicide in 1980, and he even took the Love Will Tear Us Apart singer to a graveyard to try to bring home the reality of death.
Sumner tells Uncut magazine, "I spent two weeks with him before he died. I remember talking about the first time he attempted suicide. We got the bus back (to home) and purposefully walked through the cemetery to try and bring it home to him the reality of death (sic).
"I got this idea that it had become a fantasy in his head about dying. His lyrics came from fantasy, and he would often talk about things in unrealistic ways. I thought it might bring the reality of being dead to life. (As if to say) 'This could have been you.'"