Jonnie Irwin said he first realised he wasn't well when he experienced blurred vision when driving.
The Place In The Sun presenter, 48, was given six months to live in 2020 when he was diagnosed with lung cancer, which has now sadly spread to his brain.
The father-of-three was filming the Channel 4 property show in Italy before receiving the devastating news and has now opened up about the weeks that followed.
"Within a week of flying back from filming, I was being given six months to live. I had to go home and tell my wife, who was looking after our babies, that she was on her own pretty much. That was devastating. All I could do was apologise to her. I felt so responsible," Jonnie shared.
The much-loved presenter, who shares three-year-old son Rex and two-year-old twins Rafa and Cormac with his wife Jessica, 40, has continued to work as much as possible while receiving chemotherapy.
Speaking about his decision to share the news of his diagnosis, Jonnie told Hello magazine.: “It’s got to the point now where it feels like I’m carrying a dirty secret, it’s become a monkey on my back.
“I hope that by shaking that monkey off I might inspire people who are living with life-limiting prospects to make the most of every day."
Jonnie added that while he knew his illness would 'catch up with him eventually', he was trying to 'hold that day off for as long as possible'.
Jonnie made his debut on A Place In the Sun in 2004 and fronted the show until last year as its longest-serving presenter, alongside co-star Jasmine Harman.
After the former rugby player shared his diagnosis on Instagram, Jasmine wrote: "Words can't fix much, but what lovely words of support you have had here Jonnie. I know you know this already, but I am here for you my dear friend, and Jess and the boys. So, so brave. Sending lots of love. Speak soon."
Homes Under The Hammer presenter Lucy Alexander also shared her well wishes, saying: "Jonnie. I get so much joy watching you & your boys on here. You’re one hellava flippin amazeballs presenter and I’m sending so soooo much love & strength."
Meanwhile, Escape To The Country's Nicki Chapman shared: "Love you guys so much,' while another fan wrote: "Jonnie I am so so sorry to hear your news... Life is so cruel, to the nicest of people. I send you all our love to you and your family."