The 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 took to Instagram to confirm the news and thank people for their support.
"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.
"My biggest fear is opening up to that special someone, and having my heart broken into a thousand pieces."
He continued: "But coming into this experience, I promised I would throw caution to the wind and I'd overcome that fear.
"My heart is fluttering ... and even though it could get broken into a thousand pieces, I feel the time is right to take the plunge, to take that leap and tell you how I feel. Chelsie, I love you.
"I love how you giggle when you're nervous. I love that you go full nerd as soon as there's some maths involved!"
The chemical engineer was also wearing the $30,000 commitment ring that Matt gifted her in the finale.
Chelsie has not featured a photo of Matt on her Instagram page since October 10.
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