THIS year, Siobhan Wilson tells me, has been both the worst and the best year of her life. It started off with what she calls “epic heartbreak”, which in turn led to depression. And it is ending with her knowing she's made a well-received album (Rolling Stone described it as “one of the most stunning collections of songs to be released in a long time”), and has another one nearly ready to record as well as a Celtic Connections gig to look forward to in the new year. Everything has changed.

“My album There Are No Saints has been a bit of a game-changer,” Wilson says between sips of red wine in Sarti’s in Glasgow. “I don’t know exactly why.”

I think it might be because she has taken all that dark stuff that happened to her at the start of the year and turned it into songs. “Maybe I’ve taken a step forward. I’ve been a bit braver,” she concedes. “I’ve put myself out there.”

Who is Siobhan Wilson, some readers may be asking. Well, as she is sitting opposite me this December Friday afternoon, let’s ask her. “Who is Siobhan Wilson? I am a singer-songwriter, composer, Francophone. I’m INFJ …”

Come again, Siobhan. INFJ? “Do you subscribe to those personality tests? The Myers Briggs 16 personality test? It’s basically a horoscope for psychology. You do this test and it tells you if you’re an introvert or an extrovert.”

Which is she? An introverted show-off perhaps. To be honest, I have to look up INFJ later. “Introverted, Intuitive, Feeling, Judging,” Google tells me. The first three, at least, sound like the woman I have just met.

Wilson is young (she does tell me her age but doesn’t want me to tell you. “Say 75,” she says), but looks younger than her years. In conversation she is a little quirky, but entertaining and honest. I keep thinking “Annie Hall with a Scottish accent”.

The Siobhan Wilson crib sheet goes like this. Raised in Elgin, wins a scholarship to St Mary’s Music School in Edinburgh at the age of 16, decamps to Paris at 18 to become a nanny, learns the language, sings in French, falls in love, falls out of love, returns to Glasgow and now lives in Edinburgh where she is doing a part-time Masters in composition for screen when she’s not on a stage. Oh, and she also really loves Pearl Jam.

“I’m an artist and a classical musician,” she says, completing the introductions. “That’s my background. But I spend most of my time as a singer-songwriter with an electric guitar. I like dabbling in a lot of different genres and just getting involved in everything that’s going on.”

That means playing cello with Aidan Moffat and RM Hubbert, turning up on the Cerys Matthews 6 Music show to perform live on the radio and getting ready to play with the Demi Octet at the Mackintosh Church as part of Celtic Connections at the start of February.

So many irons in the fire. “I get bored with stuff,” she admits, “So, I have to do everything at the same time. That’s why I like writing. It’s like drawing on all those different things and spitting it back out. And I never have the concentration and dedication to learn one instrument.”

Umm, learning to play cello, piano and guitar suggests a form of dedication. “In a sense, yeah, I guess. It’s funny. I got grade eight on the cello, grade eight on the piano, but I don’t use any of that for singing and that’s my job. And once you’ve done [grade] eight there’s no nine.”

Well, here’s another question. Is the composer a different person from the singer-songwriter? “I kind of wish that they were, but they’re not. It all ends up as the same thing.”

How do you know what’s a composition and what’s a song while you’re writing them then? “That’s a really amazing question and I don’t know how to answer it. I would say they’re all compositions. What makes a song a song? Do they need words? Mendelssohn did songs without words. It’s like that Magritte picture, Ceci N'est Pas Une Pipe. Is it a picture or a pipe? Is it a song or a song about a song? Talking about songwriting … Sometimes it’s easier to sing it.”

What she will say is that a song is a more informal way of representing how you see the world. “It’s a more familiar, lovely way of doing it. It’s like having a chat and a pint instead of going out for Christmas dinner.”

She’s done four Celtic Connections since returning to Scotland from Paris five years ago. And yet she doesn’t see herself as a folk musician. “But I really fit into the folk vibe.”

And that’s a good thing. “Folk is super punk. Celtic Connections is a little bit punk, right? They just shove people on stage who have never met. And they party so much harder than anyone else on the music scene.”

Siobhan Wilson was born in the last century, grew up in Elgin playing cello and piano and listening to her parents’ record collection: James Taylor, Joni Mitchell, 1970s folk rock. She was, she says, desperately shy as a child. And yet, at 16, she left home for a scholarship in Edinburgh. Two years later she decided to go to Paris even though she didn’t speak the language.

Why Paris? “It was kind of the closest place that wasn’t Britain. It’s not that far away, France. I got a Eurostar there. I was on a jazz folk band tour thing in London and I just popped over and I got a job as a nanny. A sort of musical nanny. And I loved it. It was awesome. It just felt like a bit of a change really. Not so much an escape, more: ‘What’s out there in the world?’ Everywhere else felt scary, but France didn’t feel that far away because you could just fly back.

“We’d been to the south of France quite a lot. My mum and dad live in Paris now, which is weird. Mum speaks French and loves France and I guess that rubbed off on me. And, really, when you get there I just think it feels the same as here, even though it’s a different language and there are slight differences in behaviour and in humour. But people are really all the same when it comes down to it.”

In Paris she nannied for a few years, even worked in a souvenir shop for a while and met her (now ex) boyfriend, musician Simon Campocasso.

“It was this really cool adventure. He had a studio in his flat, he had built his own computer because he was really into tech stuff and I kind of ended up staying so long because I moved in with him.

“And he wrote one of the songs on the album [Paris est Blanche], which is nice. So, yeah, he was probably my biggest musical influence.”

When she went to Paris she didn’t know who Serge Gainsbourg was and had never heard of Francoise Hardy. And yet when you hear her sing in French she sounds as if she has just stepped straight out of a bar in Montparnasse.

Does geographical context affect the music, I wonder? “Yes. When you are in the environment that totally rubs off on you. Singing in French is cool. They always pout. When I sing in French I’m always …” She puckers her lip in a particularly Gallic way. And then takes another sip of wine.

What did living in another country teach her about herself, I ask? “That I wasn’t as shy as I thought. And to be more confident, sociable,” Wilson says.

And yet she left home at 16. That implies an independent streak, an inner confidence, surely?

“Yeah, it’s weird. Doesn’t everyone have that conflict in themselves?

"You are always wanting to get more life experiences and be more confident and ambitious and you’ve always got to break barriers. I got terrible stage fright and nerves my whole childhood any time I had to play the cello. I don’t know why, but I used to find it terrifying. And I was quite shy when I was a kid and it’s only this year that I’ve stopped being shy on stage or nervous. Six, nine months ago."

So, what changed? “I think making a decision to just go: ‘Right, this is not going to happen any more'.”

She simply made a conscious choice not to be frightened? “I did, yeah. I got really sad at the start of the year because I got depression. And I think when you’re so low sometimes you come back a lot stronger. And after that I wasn’t scared of most of the things I’d been scared of last year. I feel really lucky to be here and, actually, this is f****** awesome. People are sitting and clapping and having a nice time and so am I.”

She smiles. “But that’s not really confidence is it? Maybe it’s a Scottish thing. You just assume everyone hates you, you assume it’s rubbish, and then you are always surprised at the end when they clap.”

Heartbreak and depression are at the dark heart of her album There Are No Saints. Putting this stuff out into the world definitely helps, she says. “A problem shared is a problem halved.”

“But it’s not something I want to focus on because I don’t want to be shrouded in negativity. I’ve got quite a happy life and I’m really happy onstage, so it’s funny this contrast between that and the bleak songs.

“I think it’s cool to sing about heartbreak and depression if that’s what is going on in your life because you’re talking about a lot of things that people don’t dare talk about much. It’s this big taboo and stigma.

“Everyone I know has it in some way. That’s what heartbreak is. You don’t go to the doctor to be told you’re heartbroken. But, yeah, coping strategies for surviving all of life should involve art.”

One of her own coping strategies is studying contemporary classical composition, partly, she says, because she’s interested in soundtracks, partly because her mum told me to do it.

“She was like: ‘You’re not using your brain enough.’ She was right. Mums are always right about things like that. And I love it. It’s amazing. I’ve never really been to uni before, so I was amazed they let me in to do a masters. Edinburgh University is amazing, they’ve got studios there. That’s where I’ve written my new album. I’ve got access to a recording studio as part of my masters it’s great. I’m there all the time.”

And if Steven Spielberg gives her a call and asks if she's up for writing the soundtrack for his next movie? “Yeah," she laughs. “Totally. I would do that. For a fee. I’ve never earned much money from what I do.”

Finance apart, Wilson is in a good place. “There’s nothing that I am doing just now that I don’t think I should be, and there’s nothing that I think: ‘Oh, I wish I was doing that.’ I’m 24/7 working constantly. I suppose the ambition is just to keep it all going.

“That’s the hard bit. I’ve got a manager now. Maybe he’ll do that.”

Siobhan Wilson Band and the Demi Octet play the Mackintosh Church on February 3 as part of Celtic Connections. There Are No Saints is out now. The Sunday Herald is Celtic Connections' media partner.