“Chels and I have made some beautiful memories together that I’ll always cherish, and I wish her nothing but the absolute best.
The lengthy post continued: “However, it’s with a heavy heart that I write this. For Chels and me, our relationship hasn’t translated from filming to the real, every day world as we had hoped.
“Chels is a very special woman and I want her to find the happiness she deserves.
For those who may wonder if there’s someone else for me right now, there absolutely is not.
“It’s no one’s fault, it’s just life.
McLeod also confirmed the devastating news via her own Instagram account.
"I wish him nothing but the best," she wrote, apologising to fans who were invested in the pair's relationship.
"Thank you so much to everyone for your support and kind words over what was an exciting, rewarding, challenging and emotional journey," McLeod added.
In September Matt declared his love for Chelsie on the season finale of the hit reality-TV show.
He told Chelsie at the time: "I've never believed in such thing as the perfect woman until I met you. You encapsulate everything that I'm looking for in a woman.
The chemical engineer was also presented with a $30,000 commitment ring.
Chelsie has not featured a photo of Matt on her Instagram page since October 10.
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