I've always been a big fan of difficult girls.

When I read Ballet Shoes by Noel Streatfield at a formative age, Petrova, who wanted to fly planes and hated ballet, was the Fossil I most wanted to be. I rooted for Rizzo in Grease, not simpering Sandy. And I can still quote all of Heathers.

It's no wonder then that ever since I started my writing career on J17 magazine in 1995, I've been representing difficult girls, who reach critical mass during those turbulent teen years. I can remember all too clearly being stuck in a hinterland between childhood and being a proper grown-up. My body doing all sorts of weird things. My hormones freaking the hell out. I would spend hours weeping over friend-fallouts, indifferent boys and my GCSE coursework.

I found my solace in books inhabited by characters just like me. I was as angry as Holden Caulfield in Catcher In The Rye, as naughty as Lydia Bennett in Pride And Prejudice (thank God a militia never set up camp in Edgware) though not quite as angst ridden as Esther Greenwood in Sylvia Plath's The Bell Jar. There wasn't much teen fiction back then, but I thrilled to the moody girls and bad boys in books like He Was Bad and Give Me Back My Pride from Pan's Heartlines series.

The inner landscape of a teenage girl doesn't change from decade to decade. The letters we got on J17 proved that. Is it weird that I hate my parents? Can you get pregnant if a boy sticks his penis in your belly button? Me and my mate both fancy this boy, what should we do? I have zits on my bum and I want to die. Help! Our readers desperately wanted to be told that they were normal. THAT THIS IS WHAT BEING A TEENAGE GIRL IS MEANT TO FEEL LIKE. I wanted to make them write out those words a hundred times each day. Embroider them on cushions. Have them printed on a t-shirt. Instead I started writing YA novels and I hope my chippy heroines like Jeane from Adorkable and Isabel from Let's Get Lost have joined the ranks of other fantastically flawed girls in YA such as the dark and scabrous Emily in Tanya Byrne's Heart-Shaped Bruise or the rejected and silent Melinda in Laurie Halse Anderson's Speak.

Lately though, there's been much talk about character likeability in YA. Reviews are cropping up where YA's female protagonists are described as "whiny", "nasty and judgmental", "a right cow", "such a bitch," often from readers long out of their teens who end with the caveat, "I'm not the target reader so this might appeal more to a fifteen year old girl".

Newsflash: teenage girls have layers. They want their heroines to be relatable, which doesn't mean they have to be likeable. They long for Katniss Everdeen and Tris Prior's ability to kick ass and take down names even if they also think that they're really, really up themselves. It's why they're open-minded enough to embrace and aspire to being like the difficult girls in books. To have the quiet bravery of chaotic Eleanor in Rainbow Rowell's wonderful Eleanor And Park, or the world-weary cynicism of Poppy in Holly Bourne's Soulmates. And it's why they absolutely love, love, love Harriet Manners, the swotty, gangly outsider of Holly Smale's Geek Girl series.

The difficult girls of YA fiction, whether they're dealing with bitchy best friends or battling the forces of dystopian darkness, are a welcome antidote to drippy Bella Swan, and the legion of Bella-lites the Twilight series spawned, who will only fight for their right to love emotionally controlling boys with paranormal powers.

It does a harmful disservice to teenage girls if the books they read send a message that they need to control their messy emotions, to be measured in their speech and opinions. That it's the girls who don't make waves who deserve to be heroines.

That's why I stand with the others. The innocent, unassuming girls happy to load the dishwasher who never answer back, but who, five minutes after shucking off their parental shackles, are the terror of every other passenger on the bus as they shriek at their friends, drops swears and bellow out of the window at any hapless lad, "Oi Fitness! My mate fancies you!"

Those are the teenage girls I love to write about in all their stroppy, sweet, bitchy, gobby, shy, pain in the arse, multi-faceted glory. Because when you're a teenage girl, being difficult is your default setting.

And it's why on the wall above my desk I have two postcards. One says, "Quiet women rarely make history". The other one has a photo of an imperious looking girl and the speech-bubble, "Get out of my way, I'm fabulous."

Words to live by. Words to write by.