Sheridan Smith says her battle with anxiety "snowballed" when her father passed away.
The 36-year-old actress has admitted she has "always" struggled with the mental disorder, but she has revealed the death of her parent, Colin Smith, in December last year was the "catalyst" that made her "lose [her mind]".
Speaking openly on ITV's 'The Jonathan Ross Show', which will air on Saturday (18.11.17), the blonde-haired beauty said: "I'd been performing anyway leading up to that, and I've always had a bit of anxiety, and so I was a little bit nervous but the catalyst of it all was my dad.
" I want to say 'It's okay not to be okay' because I didn't speak about it and then it snowballed and it came to this huge head."
And the grief caused Sheridan to cancel her appearance in the musical production 'Funny Girl', which she "hated" having to do.
She explained: "It was the worst thing, I hate it and I always think 'The show must go on' and I hate letting anyone down but I think the public understood in a way that you can't choose when these things happen. It was a gradual build up when my dad got diagnosed and I just couldn't continue, I lost my mind, I completely did to the point where people were stopping me in the street and cuddling me because people understand that, it's just life. Unfortunately you can't just take time off from a show, you get a lot of abuse so that's what happened."
But almost one year since the tragedy the 'Two Pints of Lager and a Packet of Crisps' star believes she is in a "better place", and she has encouraged other people who are going through what she did to speak out.
The 'Cilla' star said: "Now I'm in a better place ... You're scared to ask for help because people think 'Oh what have you got to be worried about?' and I get it but I just think, if [me speaking out] helps one person. I've had a lot of messages from young girls. I hope it helps people... I totally take responsibility for that time.
"But I've taken time away, stepped away, managed to be around my family, have some quality time with them and come back with this album and a tour and hope that people welcome me back.
"It's a weird thing because people just go, 'Pull yourself together' and that's the worst thing you can say... You can't help it. Unfortunately it just comes. It's an issue that I have that I'm working on."
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