Sarah Harding told fans she is fighting as hard as she can as she thanked them for their support following her cancer diagnosis.
The former Girls Aloud star revealed in August that she had been diagnosed with breast cancer and that it had spread to other parts of her body.
She has now updated fans in a post on Twitter, saying that although things were “tough right now”, the love and support had been “a huge source of strength”.
“Hi everyone,” said the singer. “Thank you so much for all the messages of love and support that I’ve received since my last post. Everyone has been so kind and reading your comments and DMs has been such a huge source of strength to me.
“I can’t deny that things are tough right now but I’m fighting as hard as I possibly can and being as brave as I know how.”
Harding, 39, also shared that she is penning a book about her life and that it is giving her something positive to do.
She wrote: “In September the lovely people at Ebury Publishing asked me if I’d be interested in writing a book about my life story.
Watch: Sarah Harding battling advanced cancer
“It came at such a good time as it’s given me something fun & positive to focus on while I’ve been stuck at home in between trips to the hospital for treatment.
“I’ve nearly finished it now and this week Mum and I have been looking though old photos, choosing which ones to include.
“It’ll be out after Christmas and I’m really proud of it.
“I hope you’ll like it.”
“Sending lots of love to everyone – I hope you’re all keeping well - S x,” she added.
Harding rose to fame in the girl band alongside Cheryl, Nadine Coyle, Nicola Roberts and Kimberley Walsh after winning Popstars: The Rivals in 2002.
She has also enjoyed an acting career, appearing in BBC drama Freefall in 2009 with Dominic Cooper and making a guest appearance in Coronation Street in 2015.
The star took part in Channel 4 winter sports reality show The Jump in 2016 but was forced to pull out mid-series after injuring her knee in a training session.
Watch: Al Murray taking on role of drummer in charity gig to support blood cancer patients
Additional reporting by PA.