Ria Cooper, 18, from Hull, has had thousands of pounds worth of NHS treatment involving hormonal injections to turn her from a boy into a girl.
But the hormones affected her so badly that she attempted suicide twice. Ria, formerly known as Brad, lives her life as a female.
She has developed breasts, wears her hair in a feminine bob and has dated several young men. But now she questions whether she was too young to be allowed to swap sexes in the first place.
"Life has really got on top of me recently," she told the Sunday Mirror.
"The hormones have made me feel up and down. One minute I feel moody and the next minute I feel really happy.
"A couple of months ago I'd had enough and took a lot of paracetamol but my friend found me and made me sick. Just before that, I'd tried to slash my wrists and ended up in hospital. I get these dark moods when nothing seems right.
"The night I tried to slash my wrists I d downed a bottle of Jack Daniel's and just thought about how alone I am, how my decision has alienated my family and how I will have to become a boy again to resolve it.
I don't want to live in isolation, away from everyone I love. This is the only way forward. I just want to be happy and this is my last chance.
From the age of 12, Ria was convinced she was a girl trapped in a boy's body, so when she was 15, she was referred to a psychologist at Hull Royal Infirmary and later to the Gender Identity Clinic in London.
She started hormone treatment when she was 17, making her the youngest ever patient in the UK to receive such treatment. But she says her decision has had disastrous consequences. She has fallen out with family, got into dangerous situations with men and even worked as a prostitute.
She is booked in for the full transgender operation in January but now says she will no longer go ahead with it.
She said: "I just can't be what I want to be. My mum Elaine loves and supports me as much as she can, yet she doesn't allow me to live at home any more. My dad barely speaks to me and says I'm an embarrassment.
"I think as the only boy in the family he thought I'd follow him into the steel business and pictured us working out together at the gym.
"Obviously it s not turned out like that. I don't know who I can trust as friends. I feel really, really alone."
The Sunday Mirror said that critics warned two years ago that Ria's tender years meant she was too young to make the decision to become a woman.
Child psychologist Karen Sherr, formerly of Great Ormond Street Hospital, said: "It's absolutely ludicrous for young kids to make such huge, life-changing decisions... and for doctors and their parents to support it.
"At that age you haven't developed fully, neither physically nor emotionally.
"Children need to be allowed to grow into adults before they go through with something like a sex change because, as this case shows, at that age you don t know yourself well enough."
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