In her Sunday post, Pixie shared a series of photos of the pair partying together alongside a broken heart emoji.
Singer Pixie, 29, met Caroline, 40, when they both starred on the 2014 series of Strictly Come Dancing. Caroline went on the win the series.
Friends: Pixie Lott has posed photos of her friendship with Caroline Flack in an Instagram tribute, following the Love Island presenter’s death on Saturday
Pixie shared selfies of her and Caroline on nights out, including one showing the Love Island star holding her Strictly trophy as Pixie wrapped her arms around her.
She captioned the post with a simple broken heart emoji, leading her friends including reality star Joey Essex and actress Anna Friel to offer words of support in the comments.
Caroline died on Saturday at her new flat in Stoke Newington, London, hours after she was told she would face trial over the alleged assault of boyfriend Lewis Burton last year – while the producer friend who was staying with her went to the shops.
Co-stars: Singer Pixie, 29, met Caroline, 40, when they both starred on the 2014 series of Strictly Come Dancing
The producer friend couldn’t get back into the flat when she returned.
She called Flack’s father Ian who gained entry to the flat where he found the star’s body.
Her management team have since described her as ‘vulnerable’ and criticised the CPS for pushing ahead with a pending court case despite her boyfriend saying he did not want to press charges.
It emerged on Sunday that Caroline had warned police she would take her own life.
Loss: In her Sunday post, Pixie shared a series of photos of the pair partying together alongside a broken heart emoji
The star was taking anti-depressants as she battled mental health problems and was terrified of the prospect of her upcoming trial.
It was claimed yesterday paramedics had been sent to her home the day before she was found dead, following fears for her welfare, but she was not taken to hospital.
The distraught TV presenter was understood to be horrified by the prospect of a ‘show trial’ over an alleged assault on her boyfriend and was worried she could not cope with the fallout.
Close: Pixie shared selfies of her and Caroline on nights out including one repost from Caroline which included her late friend’s nickname for her
Tribute: Caroline died on Saturday at her new flat in Stoke Newington, London
Friends said she was tormented over the idea of a jury being shown police ‘body cam’ footage taken during the night she was accused of attacking Lewis Burton, 27. She had hope the trial would not go ahead.
A court had heard police found the pair covered in blood and that Miss Flack had cuts to her wrist. The revelations about her mental health prompted questions about whether she was given enough help to tackle her depression and panic attacks.
As stars paid tribute to the Love Island presenter, friends asked if prosecutors, medical professionals and her former bosses at ITV had missed chances to save her.
ITV cancelled scheduled Love Island episodes over the weekend but said the show would return tonight with a tribute to Miss Flack, who presented five series before stepping back following her arrest.
Career highlight: Caroline and Pixie met when they both starred on BBC show Strictly, with Caroline going onto win the series with her dance partner Pasha Kovalev