Cerys Matthews: 'My marriage is over. I'm coming home'

Cerys Matthews seemed to have the perfect life as a rock star in America. Now she is back in Wales and releasing an album in Welsh. Here she reveals why

Cerys Matthews is singing in Welsh. Softly, almost under her breath, because we are sitting outside a pub in a harbour in Pembrokeshire and two old men are arguing in the same language beside us. 'Llawn iawn yw'r mor...' she sings and it is really beautiful. What does it mean? "It's an old song that says I would be as full of love for you as an egg is full of yellow and white."

That works for me. The sun is shining, the sea is glittering in the distance and one of Wales's most talented daughters is crooning a love song. It works for the old men too: they've gone silent and are both listening. What's the Welsh for "Shame she's got a husband"? Hang on though, where is he?

Everyone around here knows Cerys, the only star in the village. She has been coming to see her parents in a farmhouse high on the hill behind us since before she had hits with her band Catatonia and got a reputation as the hard-living, full-throated wild child of Britpop. The villagers all know she went away to America six years ago to escape the pressures of intense fame (not to mention a flirtation with heroin) and fell for a Nashville muso called Seth Riddle.

The couple were married in a local chapel, and held their reception in this pub before returning to the capital of country music. She's come back again now though, to live. Her children – two-year-old Johnny Tupelo Jones and four-year-old Glenys Pearl Y-Felin – are with their grandma up at the house. Cerys arrived last night. "I still haven't unpacked," she says, halfway between a laugh and a jet-lagged yawn. "Not a single bag. It's when you unpack that the chaos spills out, and I'm not ready for that."

Cerys was in London before that to promote an unlikely but successful duet with the clean-cut former choirboy Aled Jones. Tomorrow she will make another wilful move by releasing a record entirely in Welsh. She will also take Pearl to her new bilingual school in the next village for the first time. So when is Seth going to arrive? The gulls circle overhead. Cerys slumps in her chair and stares at her glass of white wine from behind huge pink wraparound sunglasses. "Well," she says quietly. "I am now divorced."

That's news to me, and I have read everything anyone has written about her recently. This split is not public knowledge, is it? "No, not really. I've not done an interview about it. What am I meant to say?"

The sun seems to have gone in. Judging by her mood we had better brace ourselves for hail stones. I am still going to ask, though, if that's why she's back. Which came first: the split or the decision to return? "Erm," she says slowly, "they both became apparent at the same time."

Cerys seems to have been restless all her life. She was born in Cardiff and raised in Swansea before her parents moved here to Pembrokeshire. She was a nanny in Spain for a while before joining Catatonia. The band toured with songs like "Road Rage" and "Mulder and Scully" then split up in 2001 – partly because Cerys was not coping. She went into rehab, then off to live in a shack in the Tennessee mountains where she made some charming music for the country-stained album Cockahoop. As always, she managed to sound both innocent and like wicked fun at the same time. Marriage and babies followed but she says, "I was always going to come back. It's a long way from Pembrokeshire to Nashville. The pull for me was my children and the freedom they have here."

Her father's family comes from here. "The pub in the next village is where my great-grandmother was born," she says, and a cousin grazes his cows on her dad's land. Mr Matthews was taught to speak only English when he was young – "in order to get on" – and became a surgeon before retiring back to the homelands north of St David's.

Pearl and Johnny Jones (he was born on the floor by the dishwasher in Nashville when she had expected to be at a Tom Jones concert) will both be brought up to speak Welsh. Cerys hopes they'll lose their Tennessee twang. "In Nashville I was always an immigrant with two young children," she says. "I really did love it, I was at home there as an adult. I would have stayed, but I didn't feel ready for my children to not have the same background as me."

You want your mum around too when you have young children, don't you? "Hmm. Yeah," she says. "And this place also feels a long way from everything. I like that, for children. I don't want to rush them into growing old. I want to protect their wildness and innocence and safety as long as I can."

She's glad we're not talking about the divorce any more. It's a difficult subject, clearly. She can usually relax here, drinking among people she knows well. Only subtle things mark her out as different from them: the sunglasses; the expensively tousled blonde hair; the suede pixie boots with heels and the T-shirt which has a union flag on the front but comes from a US soccer camp. The shades are staying on. You may as well be hung for a sheep as a lamb, as the farmers of Pembrokeshire almost certainly don't say, so here's another annoying question for you Cerys: are you going to the jungle?

"Everyone asks me this," she says, irritably. A tabloid newspaper reported as fact that she was going to be on the next series of I'm A Celebrity, Get Me Out Of Here! "It's not a fact," she says grumpily. "I'm not on the blinking 'dancing with the stars' thing and they said I was going to be on there as well. I've only been in the country three days and they've got me on every single show."

Is that so bad? They could have forgotten her. Instead it's clear that people still think warmly of good old free-spirited Cerys of the powerful lungs. "Yes, OK," she says, sipping her drink. "It is nice for people to ask, I suppose."

She sits up. "You haven't asked me about my record with Aled yet!" True, because I feel I know all I need to know. The song called "Some Kind of Wonderful" was first recorded by The Drifters and is a cute reversal of roles: usually in a duet it's the woman who provides the clear, pure voice and the man who sounds worldly wise.

The duet is clever and is proving that she can still sell a lot of records. But some people will say making a Welsh mini-album, Awyren, is commercially bonkers. Only 750,000 people in Britain will be able to understand it. "I don't care," says Cerys. "I did it for the love of the language, and the sounds of the language. I love going to Japanese karaoke bars and hearing the classics in Japanese."

Liberated from meaning for most of us, her voice becomes another instrument on surprisingly ethereal songs. Will there be a translation on the sleeve? "No," she says firmly. Why not? "Because it's beautiful. I've translated one word on the title: awyren means aeroplane. There. That's enough to keep you going."

Won't she say what the songs are about then? "Well... 'Y Corryn Ar Pry' means the spider and the fly. That's a real simple song about temptation. 'Awyren' is a dream song: I don't need aeroplanes because I just have to see you and I'm up and away. 'Lisa Lan' is a real old song, about a very poor farm boy who's just desperate for a shag. 'Trwy'r Dyrch'? Slowly, slowly wins the race. So there you go."

Catatonia was a very Welsh band, from the way Cerys rolled her r's on "Road Rage" to the chorus of "International Velvet": "Deffrwch Cymry cysglyd gwlad y gan – Every day when I wake up, I thank the Lord I'm Welsh." They were part of a great burst of Welsh creativity in the Nineties that included Gorky's Zygotic Mynci and the Super Furry Animals.

"We were blessed with that freedom by our parents," says Cerys, whose mother chose to learn to speak Welsh during the Seventies, when it was a political act. The dying language was saved by association with rebellion against the control and influence of the English. Activists campaigned hard for their own national television station (S4C which started in 1982) by staging sit-ins at studios, climbing transmitters to damage equipment and even threatening hunger strikes.

"The people who protested were pretty left wing," says Cerys. "Their kids were emancipated too. We camped with them at the Eisteddfod and were able to really feed on their feast. That's why what is happening now kind of goes against the grain."

She means the rule – won by the protest generation – that every schoolchild in Wales must learn Welsh until the age of 16. Doesn't it make her son and daughter likely to rebel against the language? "Exactly! But what do you do, ban it again? You can't be liberal when it comes to a minority language, you have to have certain rules or it will die out... but I'm so naturally against rules that I struggle with it all."

Literary Welsh is preserved by an even fiercer set of strictures made by "some cobweb-laden bard man with halitosis somewhere in a cupboard" she says, laughing. "I love Welsh and I hate it. I almost wish there was no language here, because you're born with an inherent responsibility to keep it going. That requires determination, discipline, will, responsibility, attention... all those things I find quite difficult!"

Cerys is now 38 years old. She has lived the rock and roll lifestyle to visible excess and backed off. She asks for a cigarette, despite not being a smoker. Why? Because you're not allowed to smoke in pubs any more. "It's that rules thing, I guess." Old rebels don't die, it seems, they just kick against smoking bans and the arcane rules of the world's fussiest language.

And they sing simple, direct songs. Known for world-weary, darkly funny lyrics in English, Cerys Matthews finds "an innocence I can reach only in Welsh". Relaxing now, she begins to sing about the egg again, declaring herself to be as full of love as the trees are full of leaves or the sea is full of shells. Her marriage may be over but here on the coast, with friends in the pub and her parents and children close by, the words of that old Welsh song are easy to believe.

Further listening: 'Awyren' is released tomorrow on the My Kung Fu label, price £7.99