Will Young was diagnosed with PTSD (Post Traumatic Stress Disorder) after battling self doubt and anxiety.
The 36-year-old singer sought treatment at the residential trauma centre, Khiron House in Oxfordshire, in 2012 where he was diagnosed with a range of issues including PTSD, depersonalisation and derealisation.
In an interview with The Times, he said: "My brain had shut down due to overwhelming levels of anxiety. I couldn't even recognise my own face in a mirror. It was terrifying. It's basically an extreme fight-or-flight response."
Will - who shot to fame when he won 'Pop Idol' in 2002 - blamed a number of issues for his disorders, including being bullied, hiding his homosexuality, separation from his twin Rupert at birth and addictions including love and shopping.
He said: "All those things, added to the fact that I am an insecure creative performer, made me a therapist's smorgasbord."
However, Will insisted that seeking treatment has made him appreciate his success and realise how lucky he is.
He explained: "I've really developed my view of fame and success.
"Basically it boils down to this: saying, 'Oh no, how am I supposed to handle all this attention?' is not really an option any more. Singers get paid well and loaded down with free stuff.
"If you don't like it, stop being famous. It's not a tough job. You are not changing the world. If you can't handle it, walk away."