The late 'Careless Whisper' hitmaker – who tragically passed away last month at his home in Goring-on-Thames, Oxon aged 53 – and his 43-year-old partner had reportedly split up in 2015, although the Wham! band member is believed to have "relied" on Fadi following their break up.
Speaking about the pair's relationship, a source close to George told The Sun: "George relied on Fadi for many things.
"But they had been estranged for 18 months."
And Fadi – who had embarked on a romance with George in 2009 following his split from his former partner Kenny Goss – has revealed he "never" saw George on Christmas Eve, which was the night the vocalist died in his sleep because he was asleep in his car.
Speaking previously, Fadi said: "I fell asleep in my car and I never saw him that night."
Although Fadi took to social media to pay tribute to the 'Last Christmas' hitmaker, he has since deleted his Twitter account after hackers posted messages on his account claiming the late star killed himself.
The messages on his account stated: "Not sure who that nasty close friend of George but I was in relationship with george micheal till I found him dead in bed.
"We loved each other very much and we were together almost 24 hours a day..And finally he managed... he tried numbers of time to kill himself many times... the only thing George wanted is to DIE (sic)."
Fadi said: "I am shocked with what's going on with the Twitter thing. My Twitter account has been hacked and closed. It's a bit scary to be honest. I did not send those tweets. I woke up at 11.30am to the news. I am not going to worry about these things."