“I am still dealing with my grief,” says Lisa. “I have to tell myself every day how proud she would be.”

After losing so much weight Lisa was left with loose, saggy skin and went under the knife twice to have 1.5 stone of it removed. She knows how thrilled her mum would be for her.

Lisa has a bubbly personality (Image: Getty Images Europe)
Lisa before she had surgery to have her saggy skin removed (Image: ITV)

“I can honestly see my mum on holiday in Lanzarote and she would look at me in my bathing suit now in utter shock that I have done it.

“I’ve lost the weight, had the ops, I’m sticking to my food plan and training like mad in the gym. Everything is becoming muscle and toned in the right places. I think my mum would be blown away.”

Cath Riley was a powerhouse of a woman. Witty, intelligent, opinionated, and Lisa’s biggest champion.

If anyone criticised Lisa, Cath would be like a lioness protecting her cub. Lisa knows her mum tried to encourage her to lose weight, all the time insisting she was happy with Lisa as she was.

Lisa shows off her post surgery body (Image: ITV)

So instead of drawing battle lines between them, Cath did what she did best, and backed her daughter 100%.

“My mum did take me to the dietitian­,” says Lisa. “But I think it got to the stage where it was falling on deaf ears so she became my champion. She got so used to me saying ‘I’m happy being big,’ she didn’t want to battle with me.”

Lisa got her big break as Mandy Dingle in Emmerdale in 1995, and not only threw herself into the role but also the partying, showbiz lifestyle that came with it.

After Emmerdale she took over as host on You’ve Been Framed, with her infectious personality helping pull in huge viewing figures.

Lisa with her beloved mum, Cath (Image: Contact Pictures)

Her weight started to balloon as her career soared. But when her mum was diagnosed­ with cancer in 2000, Lisa believes she also started to use food as a crutch.

“I got Emmerdale, and my mum got diagnosed with cancer for the first time. In those 11 years I just got bigger and bigger. Was it an inner realisation she was going to go?

“I fell into the party lifestyle at Emmerdale, I never cooked, everything was convenience food and microwave meals. I just got used to being that big girl off the box.

“It didn’t matter I was big. I was accepted, people liked that about me. I hadn’t succumbed to pressures to look a certain way.

Lisa shows off her amazing weight loss

“But my mum was honest with me. We used to watch Cracker and Prime Suspect. I used to say to her, ‘I would give anything to play Jane Tennison, Mum.’

“And she used to tell me straight – ‘you would never get that role because you are too fat’. Now I wish she could see I could play roles like that now.

“The last thing my mum saw me in was playing Ruth in Calendar Girls, the big, fat, funny one. Now I am playing roles where I don’t have to be the fat funny one. I wish mum was here to see it.”

When Cath passed away in 2012, she knew Lisa had landed the Strictly Come Dancing Job that was to propel her to even greater stardom.

Cath never got to see Lisa wow the judges on the Strictly stage – but she already knew her daughter was going to do just that.

And it was on the Strictly ballroom floor Lisa got the first taste of weight loss thanks to a punishing training schedule.

But it was her dad Terry being diagnosed with Type 2 diabetes that sparked Lisa’s whole lifestyle change.

Two years ago this month, she stopped drinking and swapped her favourite diet of pasta, crisps and cakes for porridge, fish and veg.

Lisa as a bridesmaid

Lisa may no longer have her mum to support her, but she has a new soulmate in her partner of three years.

Preferring to avoid the limelight­, he has been by Lisa’s side as she worked to lose weight and struggled with the prospect­ of surgery.

He was the last person she spoke to before she went under the knife, and was there to comfort her when she came round. Lisa’s eyes light up as she talks about the man who has helped her to smile again after the loss of her mum.

“I couldn’t have done it without him. He gives me a sense of backbone­.

Lisa says she used food as her crutch after her mum fell ill

“When my leg was weeping after surgery and I couldn’t do anything, when I couldn’t go to work, when I had down days, he was there for me.

“He was so patient. He met me when I was big and he loved me then, but I think he prefers me now!

“It is two years since I had an ­alcoholic drink. He got me a little card and two yellow roses. His pride in me means everything.”

On Friday when Lisa was Maid of Honour at the wedding of close friend Nicola, she wore an off-the-peg, size 12 bridesmaid dress.

Lisa before she shed the pounds

She says: “Last time I was a bridesmaid 13 years ago I had a special dress made. I ruined the pictures. This time I felt like a million dollars.”

Lisa Riley’s Baggy Body Club is on ITV1, 9pm on Tuesday September 5.

How my friend found the will to get in shape

By Amanda Killelea

I have known Lisa for more than 20 years. She is one of my closest friends and godmother to my youngest daughter Lola.

Lisa always insisted she was fat and happy. And she is such a good actress that even we, her closest friends, believed her. We had no idea that deep down she was very unhappy and wanted to change.

She was the ultimate party girl, first to the bar and last to leave. So we were all shocked when two years ago Lisa gave up drink and began her fitness regime.

We were convinced it would not last, but we have had to eat our words and then some.

Claims that Lisa only lost weight thanks to a secret gastric band are rubbish. She’s done it on her own.

I know how unhappy the loose skin made Lisa feel. One day she showed me the huge, saggy flap on her stomach.

I knew surgery was the only option, though the idea of never waking up from anaesthetic terrified her. But, never one for half measures, Lisa decided to make a documentary about it.

She asked her friends, including me, to take part. Now Lisa has the body none of us ever dreamed she would have. But the changes aren’t just physical … she is the happiest we have ever seen.