Wendy was hardly a name at all before the publication of Peter Pan, and Darren pretty much unheard of in Britain until the American sitcom Bewitched introduced us to the husband of the nose-wiggling Samantha. Maybe we should now brace ourselves for a generation of girls named Dorcas. It may not be the prettiest of names, but Julia Sawalha's portrayal of Dorcas Lane has surely won many hearts among the six million people who have been watching Lark Rise to Candleford over the past 11 weeks. Easter Day sees the final instalment when - if something so gentle permits such a crude summary - it is crunch time for the postmistress. Will Dorcas sell up and flee Candleford for Mr Delafield, her schoolmaster suitor? Or will she stick around and continue mooning after the local squire, Sir Timothy? It's not a cliffhanger in the way that 24 does cliffhangers, but I really want to find out.

I tell Sawalha that although at first I found the series slow, I have become fascinated by the Timothy-Dorcas relationship. Sawalha, who believes in some unlikely things but not the sincerity of journalists, looks sceptical. “Do you think? It's the same old thing, though. I've seen it so many times in so many programmes, that will they, won't they?” But the dilemma is so much of its (the Victorian) age: Dorcas wasting her life, as women used to, on a man she will never possess. “But she doesn't have to waste her life! I kind of had a bit of trouble with it. Being a modern woman, you look at the pros and cons and I don't think I've ever been so deeply in love where I would rather be desperate and alone. I couldn't relate to that at all. It was really hard.” It sounds as if the one person not in love with Dorcas is the actor who plays her.

Did she want to shake Dorcas by the shoulders and tell her to wake up? “Well, no, but there were times I worried that I'd come across too sickly sweet and too perfect. So there were some scenes where I said to the director, ‘I've decided Dorcas is premenstrual in this scene'. The women must have had premenstrual tension, you know.”

Whatever Sawalha's reservations, Dorcas has laid to rest the ghost of Saffy, Edina Monsoon's bossy daughter, whom she first played 15 years ago. People come up to her to say they love Dorcas without even mentioning Absolutely Fabulous. But if Edina's plain, puritanical daughter was nothing like the much-lusted-after twentysomething Sawalha, nor does Dorcas Lane much resemble her today. With Sawalha now living in the West Country, you could say that they both prefer rural to city life, but there all similarity ends. Dorcas dresses with Civil Service propriety; Sawalha, sharing afternoon coffee with me in a hotel in Bath, is curvaceous in a Cath Kidston tea dress. Dorcas enunciates like an alumnus of Cheltenham Ladies' College; Sawalha even larfs in sarf Londonese. And while Dorcas is single by circumstance, Sawalha, at 39, appears to have given up on men and children. “I think I've finally come to terms with the fact that it's not going to happen. I'm single and I think that by the time I met someone - if I were ever to meet the right person, which I don't think I will, because I'm too fussy - my biological clock means that it will be too late. There are times when I think, ‘Oh, what a shame', but I don't think that's my path in this life. I don't know what my path is, but I'm happy being an auntie.

“I've got a string of disastrous relationships behind me. I don't think I'm an easy person to live with. When I split up with my boyfriend last year it was quite daunting to me, but I thought I needed to be on my own now, because I never really gave myself any time on my own. I was always with somebody, because you think that's the norm, what you have to do. And I think you have to be emotionally a very strong person to be on your own. I would say in the past six months I've suddenly got really strong and happy with my own company.”

Her friends, few of them actors, now actually get to see her. “I'm very much a person who, if I'm with someone, I get very insular in that relationship and quite co-dependent on him, which isn't good for me and isn't good for him. You stop communicating. You stop hearing each other and you forget what you've fallen in love with that person for.”

Her ex-file includes her co-star from Press Gang, Dexter Fletcher, the mad, bad Keith Allen, Richard Herring, who in a sketch announced that his ideal woman would have “the face of Julia Sawalha attached to the body of Julia Sawalha”, and Alan Davies, her co-star in Jonathan Creek. In 2004 the Daily Mail “revealed” that Davies and she had “married over the new year after a two-year courtship and, possibly, an ultimatum from Julia”. In fact, the week before they had broken up. Sawalha was angry, then amused. Remaining in less than hot pursuit, the Mail a few months ago reported that she had newly split up with her latest boyfriend, “a water gypsy” (well, he owns a barge), Rich Annetts. In fact, they had parted a year before and remain friends. Since the split she has lived alone in her cottage in a Somerset forest. I am reminded of Snow White.

Does she miss having a man in her bed? “In my bed!” she splutters. I apologise. It came out all wrong. “It's what you meant though, innit? No, I don't.” Doesn't miss being ravished? “I was missing a man with a toolkit, but then my mum bought me one.” Is “toolkit” a metaphor? “No, it's not. If you can put up a set of shelves, you're my friend.

“As far as intimacy is concerned, there are moments in your life when you think, ‘Oh, I could do with a good cuddle'. Naturally, human beings want to cohabit, I suppose, but, you know, those moments pass pretty quickly and I think, ‘Thank God, there's no one here today' because I can listen to The Archers or can do whatever I want. I think the hardest times are when you've got good news to share and you want to come in and tell someone what a brilliant day you've had. It's not the low days; it's the good days.”

Sawalha may be lost to the world of dating, but at least she is restored to that of acting. When she left for Bath in 2004 it was with the intention of giving up on a profession to which she had committed as an 11-year-old, when she joined the Italia Conti theatre school in London. It was also a break with family tradition. Her father, Nadim Sawalha, is a successful actor (Dr Shaaban Hamada in Dangerfield) as was her older sister, Nadia, now a TV presenter. But despite her Ab Fab celebrity and later success as Lydia in the Andrew Davies version of Pride and Prejudice, Julia fell out of love with her vocation. From her last project, playing Alan Davies's new sidekick, Carla, on Jonathan Creek, she derived no pleasure at all: “I was dragging myself out of bed.”

A visit to friends in Somerset so impressed her that she left her home in London and came to stay. Originally living at her agent's, she moved in with Annetts, whom she had met at the Glastonbury Festival. They stayed in Bath, then moved into Snow White's house. Scripts arrived. They did not inspire. She considered a job in the environment, a cause she identified with, but, having left school without a single O level, first embarked on some remedial education. As a preamble to an Open University degree, she took a humanities course.

“I got to the literature assignment and something just lit up in me. I was reading all these sonnets and prose and books and it was when I read Medea that I thought, ‘Oh, that part's fantastic. Oh God, I want to play that part!' Literally all that creativity woke up in me and I got goosebumps when I was reading it. I read it again and I thought, ‘No, it hasn't left me. It is in me. This is what lights my fire'.”

Hearing that Sue Birtwistle, the producer of Pride and Prejudice, was making Cranford, she told her agent that she would “walk across a back shot” to get back in. Instead, she won the small but telling role of Jessie Brown, a woman whom Dame Edna Everage might have called a tragic spinster.

“So many people said to me, ‘Oh, you look so old', And I thought, ‘Well, I am old'. People have an image that I will always be playing somebody's young daughter. So when people saw me playing the age that I am, they were shocked.”

We recite a line from Cranford: “She has lost her bloom.” How did she feel reading that in the script? “I thought, I've got to still do it. Those costumes and the lack of make-up, they don't help, and it was in HD. And, of course, if your character's ‘lost her bloom', you're not going to get much help from the lighting camera. But I am what I am. I am the age I am.”

Whether she is yet all grown up I am not so sure. She has not entirely shaken off beliefs in the paranormal fostered at home in South London not only by her father, a “spiritual” although non-church-going Bedu from Jordan, and by her English mother, Bobbie. When two friends, one of them her sister Nadia's first husband, Justin Mildwater, committed suicide ten years ago, she consultant a medium. Now she talks seriously of her cottage being haunted by a madwoman who used to walk naked around the garden 60 years ago. She is big on food fads and is now on a raw-food diet that, with its concentration on avocado, goji berries and sprouted salad, seems a little on the samey side. She has not drunk alcohol for three years. Her only concession to normality is coffee, even though “anything in a hard shell, nature did not intend us to eat”.

What has matured impressively is her relationship with Nadia. They had an almighty bust-up six years ago when Nadia, now presenter on The One Show, married the TV producer Mark Adderley and pictures of the wedding guests appeared in OK! Alan Davies, who was going out with Julia at the time and is jealous of his privacy, is supposed to have exploded, leading Nadia to call him a “miserable git”. Julia blames herself.

“We all admit there are a lot of egos flying around and things just got blown out of proportion. It's something so trivial and silly now that we don't talk about it. Somewhere down the line I used it as an excuse for all the upset that I'd felt throughout my life. Because all it is is a younger sister wanting to be with her big sister. It's as simple as that.” And the big sister finding the younger one a bit of an embarrassment? “An irritant, you know.”

She ended the feud while visiting her parents, after spotting her sister, who lives next door, with her baby. “I saw this woman who was my sister standing at the window and thought, ‘I can't do this any more'. This energy just pushed me out the door and I went up to the window. I think she thought I was going to hit her. I'm really into self-discovery and love to look at the human condition and human behaviour, and I discovered that it was a passive-aggressive way to behave.” Perhaps it is because this vital relationship is now resolved that she can afford to worry less about romance. She claims to be the happiest she has ever been.

“You always think your prince is going to come along. That doesn't happen very often. You do meet people who are in the ideal relationship, but they are rare. And most of the people I know who are in relationships work very, very hard at them. And the relationships I've been in, it's always one person's working really hard and the other one's not.” I wonder if she fell in love easily when she was younger? “Yes, I'm a passionate person, yeah.” Does she still? “No, I don't do that any more. I see it coming and I just walk away. If I'm attracted to someone, I immediately turn away and walk out of the room because I know it's only going to lead to trouble. But that may not be final. It's just how I feel today.”

It all seems to suggest that whatever happens to Dorcas on Sunday, Julia Sawalha is likely to keep her unusual maiden name for some time yet. At least, thanks to Lark Rise, it is, once again a fashionable one.

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