United Kingdom, June 24 -- Muni Long underwent an emergency double lung transplant after she was given just one week to live.

The 37-year-old Grammy-winning R+B singer, who was diagnosed with lupus in 2014, was left stunned when she was told she needed surgery to keep her alive.

Speaking about being told she only had one week to live if she didn't undergo the transplant, she said on Good Morning America: "My jaw dropped. Literally.

"I was like, 'That's rude.' But they were kind of like, 'This is not a joke. You need to make a choice. You can either go to hospice or you can get these lungs.' "

Muni was initially concerned about how her voice might be affected by the op.

But, after being "faced with [her] own mortality", she thought ab...