AS Jane McCarry prepares to say farewell to hit BBC Scotland comedy series Still Game, she admits that the finality of it hasn't quite sunk in yet. The Glasgow-born actor will light up our television screens as loveable busybody Isa Drennan for the last time this Thursday.

The young-at-heart pensioners of Craiglang are set to take their final bow (on telly at least – the real last hurrah will be with a run of stage shows at the SSE Hydro this autumn) and McCarry, 48, is sanguine as she contemplates life after Still Game.

"As with everything in life it is always sad when it comes to an end, but then life takes over – family, other jobs – so you don't really have time to reflect and you are moving onto the next thing," she muses. "I have a wee break coming up and maybe it will sink in then?

"Of course, I will miss seeing the boys [her Still Game castmates] but we keep in touch a lot. Paul Riley [who plays Winston] was on a plane coming back from Australia and he sent me a picture from when he was flying over Mount Isa. He said: 'Aww naw. I cannae get away from you …'

"It is the end of an era and we are all moving on but I think because we know the Hydro is coming up that, right now, it doesn't feel so final. Once that is finished, it will seem final."

It is 17 years since McCarry made her debut as Isa. She had previously worked with Still Game co-creators Ford Kiernan and Greg Hemphill on comedy sketch show Pulp Video in 1995 and was later among the cast for the BBC Radio Scotland series of Chewin' The Fat.

Around the time that Chewin' The Fat made the move to television, McCarry was studying for teaching qualifications and then became pregnant with her eldest son, Iain, now 16.

McCarry recalls that while she was thrilled to see Chewin' The Fat become a roaring success on the small screen, at the same time she felt secretly sad to not be part of it. Coupled with finding her feet as a mother for the first time, it proved an emotionally tumultuous time.

"I remember Greg's wife Julie [Wilson Nimmo] coming to see me when my son was just a few weeks old," she says. "I was sitting there greetin' and saying: 'I can't do this, Julie. It is too hard.'

"She replied: 'Doll, don't you worry. It is going to be fine. The baby will be fine. You will be fine. And I've got a secret for you. The boys are writing this new show called Still Game and you are going to be Isa. Greg has been telling me all about it and it is going to be amazing.'

"Then she took me to the doctors for antibiotics. Julie had not long had their son Benny, who would have been about six or seven months, and Iain was two weeks old. I remember going down to the doctors in her wee Mini Cooper to sort everything out. And she was right: it was all fine."

McCarry jokes that with hindsight it was destiny that she would be cast as nosy Isa. The signs were there from her earliest roles, including a part in the Iain Heggie play Politics In The Park.

"I was 16 and I played a pensioner," she says. "I asked my Auntie Maisie: 'Can I get your big pants?' and she said: 'Aye, hen.' I said: 'Aunt Agnes, can I get your coat?' I remember my friend's granny gave me some bits and pieces for my costume too.

"Older women have been such a big part of my life and I loved playing that pensioner. Me and Julie [Wilson Nimmo] played pensioners in sketches for Pulp Video. Bizarrely, my whole life has been pointing towards playing a pensioner.

"That is the joy of it," she adds, smiling. "If I was getting cast in the gorgeous young girl parts in my twenties, then that would all be behind me now."

McCarry has always drawn inspiration from the formidable women around her. "All these funny and strong characters. My Auntie Maisie, whenever she got on a bus, had a packet of Fruit Sensations or Mint Sensations with her. She would wink and say: "Can I offer you a wee sensation, driver?"

"I remember being at a christening and as we came out, she fell. She looked up at the minister and said: 'Here I am, a fallen woman …' She used to go to funerals of folk she didn't know just to talk to people and get a free steak pie. Somebody would always offer a lift home.

"She and my Aunt Agnes were hardworking, funny, down-to-earth and warm women. When I was younger, I would think: 'Oh, it would be great to be battering into scones …' I didn't know about type 2 diabetes in those days."

An only child, McCarry grew up on the south side of Glasgow ("right on the border of King's Park and Rutherglen"). Her late father was a train driver and her mother, now 90, worked as a newspaper secretary. McCarry has two sons: her youngest, Alexander, is 14.

She talks frankly about being part of the so-called "sandwich generation" – the 1.3 million people in the UK who face the dual responsibility of caring for their children and ageing parents.

"One of the hardest things in my life was the year before my dad died," she says. "My mum wasn't well and neither was my dad. The boys were younger and I was working while coping with hospital appointments for my mum and dad.

"I'd have the kids pushing one wheelchair and I'd be pushing the other wheelchair. I did think: 'This is insurmountable now. I actually can't do this anymore.' It became too big. But then you tell yourself, 'I'll just do today …'"​

Taking it a day at a time helped, she says, although it took an existential moment as McCarry stared out into the sea of faces while performing in Still Game at the Hydro in 2017 to gain the much-needed perspective that something tangible had to change.

"I realised that I could continue the way I was – or start saying no," she says. McCarry took stock and shed the superfluous, instead prioritising what did matter – family, enjoying her work, spending time with friends – and it felt like a weight had been lifted.

Learning to say "no" has given her space to be able to say "yes" to the things she wants to do, be it as an actor or within her personal life, McCarry adds.

Among her favourite pastimes she lists playing badminton and going out for tea with friends. "Talking is my passion," she says. "Eating and blethering is my idea of fun."

Although McCarry would be the first to assert that differs markedly from her on screen alter-ego. "Isa is a gossip and I'm not – I don't like gossiping," she says. "I stick my nose in where it isn't wanted. I chat to everybody. But passing on gossip is different to being nosy and chatty."

As for the secret behind the enduring popularity of Still Game? "It doesn't make pensioners out to be perfect," she says. "I know Ford and Greg have said that when they wrote it, they based it on their grandpas, uncles and different folk in their own lives.

"It is about funny and interesting people who, just because they are old, aren't being written off. They are the same people they have always been except they have gained all this knowledge and don't care what anybody thinks.

"They are living every moment of their lives and I think that is why people love it. They are not caricatures of old people; they are just real folk who have got older."

The final episode of Still Game will air on the new BBC Scotland channel this Thursday at 10pm