The 32-year-old Ms Gradon was found dead at her parents' address in Ponteland, Northumberland, reportedly by her boyfriend.
Officials said there was no third party involvement suspected in the 25-year-old's death.
Gradon, who was crowned Miss Great Britain in 2009 and went on to appear on the British dating show "Love Island" in 2016, was found dead in the United Kingdom on June 20.
Since Gradon's death, most of Armstrong's content on his Instagram involved pictures and videos of the two together. Former Love Island contestant Sophie Gradon was found dead on June 20th.
The day before, Armstrong shared a heart-breaking tribute to his reality-star girlfriend on social media.
He wrote on Instagram: "Just wish I could cuddle you all day miss you so much man Sophie not a minute goes by with out your gorgeous smile being a picture in my mind everyday we spent together was so unbelievable I need them days back". Aaron's cause of death has not yet been revealed, but just one day before his passing he took to Instagram to gush over his late love.
Tragedy has hit the Love Island family again.
"She had suffered from depression and anxiety and there was talk of financial issues which obviously adds to the worry she was enduring. I love you so much Sophie I will keep fighting for you".
Gradon was the only out LGBT person to ever appear on Love Island. "Thinking of his family and friends", Katie Salmon tweeted.
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