WHEN MELANIE CHISHOLM was on the dole she used to save up to buy a £3.80 Travelcard so that she could attend auditions. Once she was in Central London she would kill time by window shopping.

“We’d walk round Miss Selfridge and I always used to go, ‘One day I’m going to be able to buy anything I want in this shop.’ The funny thing now is that I can’t remember the last time I was in Miss Selfridge. I shop in Selfridges.”

Somehow Melanie C gets away with this. She doesn’t mean to sound elitist, because she isn’t, even though there’s a nice, shiny BMW Z3 outside and she is wearing one of those velour tracksuits that has a logo to remind you that it cost a bomb. These are the relatively modest trappings that come from her former incarnation as a Spice Girl: she wears her multimillions lightly.

Not long ago she bought a sofa and a dining table in the sale at John Lewis. “On my own. I was so proud of myself,” she says, and laughs. Then there was the time she saw a Cacharel top in Harvey Nichols and it was beautiful. It was also £160, and she thought “it’s not that nice”. So she doesn’t shop with an interior designer in tow, and she doesn’t pay through the nose for labels most people wouldn’t recognise. She’ll never get a Hello! contract carrying on like that.

Of course Melanie C knows exactly what is expected of celebrities, and most of it makes her squirm. But what is strange about her is that while she remains in many ways an underwhelmingly ordinary multimillionaire — not too flash, not too skinny these days, loves her mum, stays in and watches telly with her boyfriend — she is still a grafter. Why else has she just released an album and now a single? Not, I think, because she is greedy but because she has packed enough experience into the past decade to know that she is not ready to give up performing. And to know how easy it is to feel miserable when you’re not yet 30 and, by most people’s standards, have already achieved everything.

It is true that she has musical talent and can actually sing, and she is widely acknowledged as the most talented Spice. But she clearly has something else, too: the kind of steel that you need to extend a more than satisfactory pop career long after its sell-by date.

This is what makes her seem odd. We are in her publicist’s office, she is sleek, tattooed, muscular and a well-judged combination of friendly and self-contained. And so lacking in grandeur that you wonder why you haven’t met her on the bus. She seems like the working-class girl from Widnes who spent her childhood watching her mother, a club and cruise singer, and dreaming of fame. What she doesn’t quite seem like is the one who achieved it.

So there is a lack of complacency about her past success, and that makes her both likeable and, possibly, obsessive. What does she still need to prove? “I was a perfectionist. I never felt good enough,” she says. “I spent a lot of time thinking I didn’t deserve it. But now I think, well, there are more talented people than me out there but it has happened to me, so I deal with it by being very conscientious.

“I do a lot of vocal training and put the hours in because I’m trying to make myself deserve it and I’m trying to be the best artist I can be.”

If you look at her background it isn’t difficult to work out where the drive comes from. Her parents divorced when she was three, and both remarried and had more children.

“I was always very independent,” she says. “As I was growing up I wanted to do something for me, probably to make my parents proud of me. I had two families and I felt I was in the way, a spare part. When I was a teenager I used to think that if I wasn’t there it would be easier for everyone. My mum and dad only used to talk to each other because of me.”

She says this without resentment. If she seems full of anything it is grace and good sense. Given that her years with the Spice Girls brought her eating problems and depression, it would be easy to paint that time as bewildering for a jobbing dancer of 20. It wasn’t, she says. It was exciting, they were pursuing a common dream, they worked hard, they were organised, they were financially switched on.

“I’ve sat through countless meetings with lawyers going over contracts, and when you’re a kid it’s so boring but it’s so important. We had a great dynamic. Nobody pushed us about.”

But what they couldn’t control was the sense of isolation that came from being a Spice Girl and nothing else. “I slept on my own, got up, went back to work. It became the only thing in my life.” There was no social life, they didn’t see their families or friends, and, privately, Mel C started to crumble.

“You think you’re OK at the time because you’re getting by on a day-to-day basis,” she says. “But you’re so busy that you don’t really have time to think about much because you’re thinking about the next thing you’ve got to do. Then all of a sudden it catches up with you.

“I was that self-obsessed that I was oblivious to whatever was going on around me. The eating disorders made me very lonely and isolated. It’s a dirty secret, it’s terrifying. It’s an obsession, it’s exhausting, and I got myself in such a mess that it frightened me.”

The Spice Girls era was a bizarre time, she admits. “Now it’s difficult to accept that I was a part of it.” But she is not daft enough to wish it hadn’t happened, because it made her appreciate her life now, and what she values is the aspects of it that she knows are normal.

Therapy helped, but much of her sense of perspective stems from her partner, Tom Starr, a building company director. “He has helped me, probably more than he would realise, without doing much. Puts a bit of normality into your life. It’s difficult because I’m not comfortable with being famous, but I love being on stage and thousands of fans out there singing my songs.”

This isn’t a complaint, more an observation from someone who has learnt about cause, effect and compromise. Which is rather more complicated than the sentiments that the Spice Girls sang, but then Melanie C has moved on.

Melanie C’s album Reason is out now on Virgin

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