The couple met inside the Love Island villa earlier this summer and have been joined at the hip ever since.
Taking to Instagram, Dani said: “Jack and I have sadly decided to part ways.
“It’s been an incredible six months and we will always have a place in our hearts for each other but sadly we have come to the realisation that it’s not meant to be in the long term.
“We both plan to stay friends. I hope you’ll all understand.”
Jack previously admitted that their relationship wasn’t perfect and that filming their upcoming reality show and living together had made things harder.
The Essex lad said: “Filming the show wasn’t easy. It was tough, it was intense – you’re on camera most days of the week all day long.
“We had bickers during filming just like any other couple. I got emotional with Dani doing it; I even had a couple of tear ups. But Dani and I got through it.”
Jack and Dani were together for just 129 days.
Meanwhile, a source added: “They came out to a whirlwind of publicity and after a while, things started to get to them and the cracks appeared.
“They are both incredibly busy and they have decided to call time on their romance.”
In a seriously awkward turn of events, just days ago Jack and Dani were confirmed as social media hosts at the 2019 National Television Awards.
It is not yet known if they will still honour the agreement, however, their reality TV show will air as expected.
An ITV source told OK! Online: “Love Island: The Christmas Reunion was recorded last week and will still broadcast as planned.
“Jack and Dani: Life After Love Island is close to wrapping and again this will not affect the transmission.”
Sadly, Jack and Dani aren’t the first couple to split from this year’s show.
In fact, only three of the couples remain together – Josh Denzel and Kaz Crossley, Megan Barton-Hanson and Wes Nelson and Adam Collard and Zara McDermott.