Craig Park had appealed for help after Jon Paul McAllister (38) became ill while on holiday in the Indian Ocean.
The pair had been on the trip to South Africe, Madagascar and the Seycelles to celebrate the end of Mr McAllister’s chemotherapy treatment for bowel cancer and their January engagement.
Mr Park said a scan showed the treatment was shrinking the deposits left behind following surgery to remove a tumour and the couple were advised they were fine to go on the long-awaited trip.
In Madagascar, Mr McAllister’s health deteriorated rapidly and, having been transferred to improved medical facilities on nearby island Reunion, he is too sick to return home on a commercial flight.
Friends started a fundraising campaign on Friday to pay for the overseas treatment and an air ambulance flight back to Scotland, which they said the couple’s insurance will not pay out for.
Already more than half the £35,000 target has been raised.
Mr Park, who left Falkirk five years ago to live with his partner in Glasgow, said: “We are speechless. People’s kindness and generosity is amazing. We weren’t expecting this at all.”
He added that his fiance, who is a social worker, “is an amazing 38 year old guy, who has always been, and continues to be, an inspiration to so many people”.
He said: “His loyal, strong, fun, humble, determined and caring character is why we all love him and need him home where he belongs.
“Jon Paul’s huge heart has led him to live a life helping others. He has impacted on so many people’s lives, both personally, and professionally through his ten years working with children and families. We’re desperate to get Jon Paul home to receive the best treatment possible. He’s one of life’s giving people. Can you please help us give back to him?”
He never asks for anything but this is one of those times where he needs help. “Being 38 he never expected the news we received about his stage four cancer and after chemo he thought everything was ok. “It’s really taken its toll on him, and at this moment in time needs to be home, surrounded by loved ones and receiving the medical attention he deserves and needs.”