Sinitta felt like she'd "swallowed a packet of razor blades" after contracting coronavirus.
Sinitta
The 56-year-old singer - who contracted the virus during a gig in London, shortly before the UK went into lockdown - claims Simon Cowell was aware of her health troubles because of their psychic-like connection.
Speaking to the Sunday Mirror newspaper, she shared: "I caught the virus after doing a club gig. Next day I felt as if I'd swallowed a packet of razor blades.
"I was in bed for about a week. I didn't tell Simon I was ill but it wasn't long before he got in touch.
"We speak quite frequently. I didn't call as I didn't want him worried - I thought, 'Well, there's nothing he can do.'"
According to Sinitta, Simon knew she was ill before she'd revealed the news of her coronavirus diagnosis to him.
She said: "He told me, 'We have this weird connection, I can just tell when something's wrong.'"
Last year, meanwhile, Sinitta revealed Simon is her oldest friend.
The pop star explained that their enduring friendship comes from being around for each other's early successes.
She said: "We're each other's oldest friends. Our first real successes were with each other, so our journey has always been together.
"He's truly an honourable, loyal person and he's fun to be around.
"When you're in his presence he treats you like you're the most important person in the room."
Sinitta is also close with Simon's partner Lauren Silverman, with whom he has six-year-old son Eric.
She added: "I'm very happy to be part of that friendship group, though.
"He trusts me, he knows I have no agenda. It was me who got him on to the diet that led to his weight loss.
"He was starting to look unhealthy and I told him so. He took it on board because it's me. He's since told me I saved his life."
Tagged in Sinitta Simon Cowell