George Michael has insisted he is "perfectly fine".
The 52-year-old Careless Whisper singer was rumoured to have admitted himself into a Swiss rehab last month.
His cousin's wife Jackie Georgiou claimed during a recent interview with British newspaper The Sun that George had a crack cocaine problem, but he denies her allegations.
"To my lovelies, do not believe this rubbish in the papers today by someone I don't know anymore and haven't seen for nearly 18 years…" he wrote on his Twitter account Sunday July 12. "I am perfectly fine and enjoyed Wimbledon like the rest of you. Wish it went to 5 sets though!...Lots of love, The Singing Greek xxx"
Last month German magazine Bild reported George admitted himself into Switzerland-based treatment facility The Kusnacht Practice to seek help once again for smoking excessive amounts of marijuana. The paper claimed he was inhaling 25 joints per day before checking into the rehab centre.
His cousin's spouse Jackie told UK newspaper The Sun this was inaccurate, as he was coping with a major crack cocaine issue.
"He was smoking crack," she told the outlet. "Before he went away he got to the point where he would be shaking, saying 'I need it.'
"There were parties where he was taking drugs and collapsing and being picked up off the floor. Waking up in vomit, horrible things. He was so thin, so ill. It's crack, it's marijuana, it's drink, it's coke. It was pretty dark and things were getting darker. He was going to end up locked up or dead. I'm petrified he will die."
George closed out his social media message on Sunday by sending love to someone he is actually very close to.
"Love you too @samsmithworld," he wrote to 23-year-old Stay with Me singer Sam Smith.