An inquest today revealed the 32-year-old was battling depression when she ended her life with a lethal cocktail of alcohol and cocaine.
Her boyfriend Aaron Armstrong performed CPR on her for 15 minutes but was unable to save her.
North Shields Coroners Court heard how Gradon, crowned Miss Newcastle and Miss Great Britain in 2009, had been mourning the recent death of close friend Paul Burns at the time of her death.
She exchanged a series of Instagram messages with pal Sondeep Gill before the pair spoke for nearly an hour on the phone in the early hours of June 20.
Sophie said Paul "had been there for so many people and he had stopped her from taking her own life."
"I cannot do this any more I struggle every day with my ADD [attention deficit disorder]," she told Gill.
"I would never want to do that to my family but if I could escape I would. I cannot believe I am telling you this. I have been struggling with the world, no one knows why or how."
The phone suddenly went dead at 2:40 a.m., and Gill's messages went unanswered after that point.
Gill told police: "Her speech was slurred, she was repeating herself a lot and during the conversation I was worried she sounded down so I tried to keep the conversation light and told her she should go to bed."
The court heard that Sophie had been prescribed the anti-depression drug Sertraline in 2013 — and that the drug was found in her system along with the alcohol and cocaine.
Toxicology tests showed she had a blood reading of 201mg per 100ml of blood — around three times the legal driving limit, as well as cocaine.
Armstrong, 25, went on to hang himself five days after her funeral having taken a similar cocktail of cocaine and booze, a separate inquest was told last month.
Armstrong and Gradon also exchanged texts the day before her death that were "very general and loving in nature" while both were at home looking after their respective parents' dogs.
But when he couldn't contact Gradon the next day, Armstrong became so worried he called his brother Ryan and the pair went together to her home in the village of Medburn near Newcastle, arriving at around 7 p.m.
At first they threw stones up to Gradon's bedroom window to get her attention, before Armstrong peered through the living room window and saw his girlfriend was unconscious.
The brothers smashed their way in through a door before Armstrong began performing CPR.
He continued for 15 minutes while Ryan spoke to the ambulance service, until it became clear that Gradon was dead.
Coroner Eric Armstrong issued a stark warning from the North Shields court, citing research in the U.S. that said mixing drink and drugs made people 16 times more likely to kill themselves.
He said he was "certain she would not have acted as she did without taking alcohol and cocaine."
"The combination is used by those who believe it brings on a so-called high much quicker," he told the court. "What they do not appreciate is it also gives rise to violent thoughts. If Sophie's death is to serve any purpose at all, that message must go out far and wide."
Recording a narrative verdict, Mr. Armstrong said he could not be sure it was suicide, but ruled out any third party involvement.
He earlier described Aaron's thinking at the time of his death as "muddled by the distress of Sophie’s death, the distress at having found her."
His devastated mum, Donna Armstrong, described their relationship as "very intense and emotional."
The inquest was dramatically halted from its planned start on March 21 so Gradon's parents could read a new report into her death.
At the time an official was quoted saying: "Please note that it has been necessary to cancel the hearing date for the Inquest dealing with the death of Sophie Gradon. Sophie's parents have requested further time to consider a report which was only recently received."
Sources close to the family said they believed there was "nothing to support" the suicide theory, the Mail Online reports.
Her parents were not present for the hearing.
Fellow "Love Island" contestant Mike Thalassitis was also found dead last month, prompting calls from Health Secretary Matt Hancock for reality shows to do more for competitors once they have become famous.
This article originally appeared on The Sun.