A 14-year-old girl was found hanged by her parents and brother after hiding her depression from her family for months after breaking up with her boyfriend.
An inquest heard that Alara Lawson's last words before she was found in the garage of the five-bedroomed home were: "I love you mum."
The schoolgirl had left a series of heartbreaking notes, including one to her ex-boyfriend which read: "I have decided to end my life. I've suffered from depression for about three years.
"I guess keeping everything bottled up for three years just kills. I have to end this pain."
The coroner was told that the 'bubbly' teenager had broken up with a boyfriend, named only as Master X, late last year but had not spoken of being unhappy.
Instead the outwardly happy girl had repeatedly talked of the future and even about which university she might like to attend, her devastated father told the inquest.
Her father said when the family went out that tragic evening Alara's mother shouted to her daughter that they were leaving and she replied 'I love you mum'.
But when the father and his wife , 47, returned from the school open evening with their son on June 20 this year they discovered Alara's body at their home in Berkshire.
They tried to resuscitate her as they waited for ambulance crews to arrive. Paramedics rushed the youngster to the North Hampshire Hospital in Basingstoke where accident and emergency staff spent an hour trying to save her.
Dr Lawson, 62, told the inquest in Newbury that his wife and daughter had a relationship 'like best friends' and said he had 'no idea' his daughter may have been unhappy.
"It's a complete mystery and has devastated our family," he said.
In a statement, Marnie said: "Alara never showed any signs of depression and was always a happy, bubbly girl. Alara gave no indication she was about to do this.
"We have always been an open family and talked about things and Alara has been a happy, independent child."
Alara's friend, Saffi Donertas said Alara had been a 'shadow of herself' in the months before she died and had confided in her about feeling unhappy.
Police discovered photographs and pictures on the Year Nine pupil's iPod of 'emo images' depicting despair with characters crying blood and images of fallen angels.
They also found a series of essays with headings including 'Trust, 'Dark secrets', 'Time to die', 'Your fault' and 'I just want you back'.
Recording an open verdict Berkshire coroner Peter Bedford said: "What is overwhelmingly clear from the evidence is that those who knew Alara best - her family and friends and school teachers - had no expectation, no inkling, even with the benefit of hindsight, no understanding what happened to end her life at such a young age."
A Just Giving page has been set up in Alara' memory.