In recent weeks there have been a number of reports that Melanie, 47, had secretly been dating 33-year-old Olly Murs for months, after they reportedly shared racy messages.
The pair are said to have bonded over a love of fitness after being introduced by a mutual friend before enjoying a string of under-the-radar dates over the past year.
A source told The Sun: 'They were initially introduced through a mutual friend. They started texting for ages and some of the messages ended up getting quite saucy.
'Olly was getting in shape at the time and Mel really loved his new fit bod.'
But now the star has shut down the 'sh*te' that has been written about her in a defiant Instagram post in which she referred to herself as 'single'.
The mum-of-two shared a snap with her 127k Instagram followers of her looking stunning in a floor length dress, with high thigh split.
Melanie wrote: 'To all Those writing sh*te about me and my life. This is what a single, happy, healthy, 47yrs old independent mother of two teenage sons looks like. DEAL WITH IT!'
Melanie's candid post has had an overwhelming response from fans, with over 9k likes and 557 comments of support.
'Good on you. Don't anyone mess with a feisty Northern girl,' one declared whilst another added: 'you tell them mel looking fab :-)'
'Good on you @msmelaniesykes your looking amazing and doing a wonderful job,' a third commented. 'Sod the negatives. All the best for you and your boys for your future adventures 🙌🏼😘.'
Olly Murs was previously seen on Mel's Instagram earlier this year, when she shared a friendly photo with him at the O2 back in April.
Melanie is mum to 15-year-old Roman and Valentino, 13, from her marriage to actor Daniel Caltagirone, whom she split from in 2009.