Scottish Conservative leader Ruth Davidson stunned the Tory faithful last night by ruling out ever running for the party leadership.
Ms Davidson revealed that she suffered from suicidal thoughts as a teenager, and that she would not risk her mental health by running for Prime Minister.
Asked if she had her eye on No 10, the 39-year-old replied: 'No. I value my relationship and my mental health too much for it. I will not be a candidate.'
In an interview with the Sunday Times, Ms Davidson said that her teenage years were plagued by self-harm and suicidal thoughts.
She claimed her bouts of depression resembled a 'smothering black blanket over my head'.
To demonstrate that, Ms Davidson reportedly pulled up her sleeve to reveal self-harm scars on her arms.
Making clear she would not be a candidate to replace Theresa May, she said: 'You have to want it, and I don't want to be Prime Minister.'
Her refusal will lead to despair among many liberal Tories who have seen the gay, kick-boxing Edinburgh-born MSP as the salvation of their party and a better choice than rivals such as Boris Johnson.
But Ms Davidson, who is pregnant with her first child, made clear she would put her baby and partner, Jen Wilson, first and ruled out moving to Westminster.
She dismissed the prospect of heading south to become an MP or taking a peerage as 'b******s.
'On a human level, the idea that I would have a child in Edinburgh and then immediately go down to London four days a week and leave it up here is actually offensive to me,' Ms Davidson said.
Her comments came ahead of the publication of her memoirs.
Extracts published last night in the Sunday Times contain confessions of depression and alcohol abuse.
She recounts how, when she was 17 and at university, a boy from her home village killed himself.
'I went into a total tailspin. I started hurting myself: punching walls, cutting my stomach and arms with blades or broken glass, drinking far, far too much and becoming belligerent and angry.
'I was punishing myself and hating myself for it at the same time.'
Ms Davidson reveals that she was diagnosed with clinical depression at 18.
But she records how she managed to conquer the illness by building structure into her life, taking regular exercise and moderating her drinking.
And she said returning to church and 'throwing away my pills' helped her mental well-being.