Robbie Williams is estimated to be worth around £155 million, but that fame came at a serious cost.

The Angels singer has revealed he spent THREE YEARS unable to leave his sofa whilst battling Agoraphobia – a type of anxiety disorder in which you fear and avoid places or situations that might cause you to panic and make you feel trapped, helpless or embarrassed.

Opening up about the debilitating disorder, Robbie explained that he turned down a $15 million offer to host American Idol, for fear of leaving his house.

“I remember they offered me £15million to take over from Simon Cowell on American Idol, plus a big gig in the States, but I turned it down because I wasn’t leaving the sofa at the time. I just couldn’t.”

“My career had gone stratospheric and taken me to Mars, and I needed some time to get my equilibrium back and get myself back together,” he said.

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“It was my body and mind telling me I shouldn’t go anywhere, that I couldn’t do anything. It was telling me to just wait — so I literally just sat and waited.

“I was agoraphobic from around 2006 to 2009. Those years were just spent wearing a cashmere kaftan, eating Kettle Chips, growing a beard and staying in.”

It was a lightbulb moment, after hearing the song Human by The Killers on the radio, when Robbie realised he needed to “get his a**e into gear” and think about a comeback.

Thankfully, with the help of therapy and the support of his wife, Ayda Field, Robbie slowly made a return to public life.

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“I remember listening to that Killers song and something in that moment made me think, ‘I had better get my a**e in gear, put an album together and tour’”.

But, entertaining didn’t come as naturally to Robbie, 45, as it once did.

“I didn’t know what the f*** I was doing, it didn’t seem natural to me any more,” the dad-of-three explained. “I had to re-learn how to entertain. It wasn’t an easy process — it was like having a car crash and then learning how to walk again.

“If it wasn’t for Take That, and rejoining them, I don’t know if I’d have come back at all.”