Donald Storrie died on Saturday morning at Glasgow's Marie Curie Hospice – a centre which the former estate agent helped to create by spending three years tirelessly fundraising for the cause.
The 69-year-old, who sold his estate agency in 1987 for £15million, had been suffering from pulmonary fibrosis and took ill five weeks ago while on a cruise with his wife May.
Mrs Storrie said his death felt like "slamming into a brick wall" but added that it was fitting he spent his last few days in the centre that was one of his biggest achievements.
Speaking from the family home in Thorntonhall, Lanarkshire, she said: "It was all very peaceful at the end. We were all with him.
"He was a patron of Marie Curie. When the doctor mentioned the hospice, Donald said that's where he wanted to be. The nurses said to me 'this building is him' because he put so much of his life into it."
"He was a hugely charitable man, always ready to help anybody who was down on their luck."
Mr Storrie was also a devoted family man who doted on his sons Stuart and Grahame, and grandsons Jack, seven, and Bruce, five.
He was given the Sir Bill Cotton award for his contribution to Marie Curie Cancer Care.
Around 600 people are expected to attend Mr Storrie's funeral service at Orchardhill Parish Church, Giffnock, on Saturday at 11am.