"It is with a very heavy and broken heart that I have to officially announce that at 1.55am this morning Willie Thorne lost his battle and passed away! Willie went into septic shock and was not responding to any treatment so the decision was made by the hospital to turn off the machines," said Ms O'Neill.
"I was with him all the way to his end and reading out messages to him from people. He passed away very peacefully and without pain listening to his children saying they love him ❤️ that gives me some comfort in this difficult time.
Snooker star Willie Thorne
Image credit: PA Photos
"Over here in Spain everything happens very quickly so today myself and his family will he making plans and will inform you accordingly!
"It disappoints me that people were tweeting he had passed away when he was still holding on and with us! I guess that’s celebrity life....
"Thank you so very much to everyone that has been involved in Willie's care you have all been absolutely amazing and Willie couldn’t have asked for better ❤️
"Thank you for all the donations that enabled him to get the care he needed! This will now pay for his funeral. Thank you for all the well wishes and beautiful messages of support xxx"
Thorne, who lost in the 1985 UK Championship final 16-14 to Steve Davis, won his only ranking tournament at the 1985 Mercantile Credit Classic and twice reached the World Championship quarter-finals in 1982 and 1986 during a 26-year professional career that began in 1975.
The 66-year-old – nicknamed 'Mr Maximum' due to his penchant for making 147s in practice – became an established member of the BBC punditry team commentating on snooker for over two decades and appeared on the 2007 version of the light entertainment programme Strictly Come Dancing.
Thorne also fought a gambling addiction and was made bankrupt after revealing he had borrowed up to £1m as debts spiralled out of control.
It was reported in late May that the former world number seven had been unable to move his arms to answer phone calls at his rented home in the Spanish city of Alicante amid fears he could also be fighting the blood poisoning illness of sepsis during his cancer battle.
Thorne was taken to hospital on 2 May. He had since undergone three blood transfusions, and treatment for a virus amid the global coronavirus outbreak.