Imagine if you were five years old at a birthday party where the noise and the colours and the feelings were all kaleidoscoping into a swirl that made you feel sick and you couldn’t understand why everyone kept looming their huge faces right into yours and saying “Isn’t this fun? Aren’t you having fun?”.

Imagine if your happy time was hours alone quietly playing with your toy horses, drawing pictures of them, reading books about them, soaking up information quite happily until you were an encyclopaedia of knowledge.

Imagine if you met a schoolfriend in the park when you were with your mum, but you couldn’t say hello because you felt physically sick at the idea of getting the words out, even though they walked past you and you could see them catch your eye and frown slightly, as if they couldn’t quite work out why you wouldn’t speak.

Imagine if you learned to read so early and so quickly that teachers wouldn’t believe you so you learned to fake-stumble over words in school reading sessions while devouring adult books at home.

Imagine if you were sitting in the classroom, and the teacher told you she didn’t want to hear a single word from anyone for half an hour, so you sat there, watching the clock, legs crossed, knowing that you mustn’t interrupt her – until it was too late and the classroom was full of horrified amusement because you were sitting there with a puddle under your chair.

Imagine if you were trying and trying to concentrate at school, but the sound of the clock ticking was as loud to you as the teacher’s voice and the scratching of the pens and the breathing of the person next to you, so you had to work so hard to focus that it made you feel dizzy and every day you went home with a migraine.

Imagine if standing in line for school lunches every day, and the jostling and the noise made you want to cry because it was just too much, and then you went inside and the food all tasted of hot metal and washing up liquid and it made you want to throw up.

Imagine if you didn’t know where to eat at university because you couldn’t work out how the cafeteria operated so you bought expensive sandwiches from the shop every day, running down your meagre student budget which you couldn’t manage anyway because paperwork and bills didn’t make sense.

Imagine if you could hardly ever organise yourself to get to lectures, and when you did get there, you found it almost impossible to concentrate on what the lecturer was saying so you shut down, exhausted, and fell asleep.

Imagine if you spun your way through twentysomething, blocking out the world with whatever you could because when you did the noise and chaos stopped for a while.

Imagine second guessing every social interaction, watching it through a lens, checking your behaviour is okay and your conversation makes sense and your body language is matching your words. And imagine never quite knowing if someone is joking or not so you have to ask, even though you know asking means you’re not playing the game properly.

Imagine walking out of job after job – even though you were promoted, even though they thought you were talented and had potential – because pretending to cope was so hard that you’d have nothing left and you’d lie on the bed crying all night at the prospect of having to go to work.

Imagine having your first child and realising oh, this is it. You can do this. And imagine reading everything you can on parenting and being so terrified that you’ll break a rule and somehow break your child that fifteen months later, broken yourself, you walk into the doctors’ surgery and say you can’t do it any more.

Imagine the love for this solemn, owl-eyed child, who doesn’t like to be held when she’s crying and hasn’t read the same parenting rulebook. Imagine watching her at music class, refusing to join in, realising she is hating every second, crying at the noise and the lights and the chaos. Imagine wishing desperately that she wasn’t like you – that she was child in the middle of the room, dancing happily, instead of sitting in the corner, sullenly clacking on the same blue castanet every Wednesday.

Imagine discovering that there’s a thing out there that describes your child’s behaviour perfectly, and imagine the nursery school notice her behaviour and say look, we think there’s a thing here. And imagine realising when you start reading (and when you start reading, just like always, you read everything) that this thing describes you, too. But then the health visitor shakes her head and says no, look, she doesn’t line up her toys and anyway, it affects boys, not girls.

Imagine years of teaching your child everything you’ve learned about how to be a person. About what’s expected, how to behave. Imagine dealing with the exhausted after-school meltdowns, and going in and fighting your corner and saying look, this child isn’t ever going to tick the people pleasing boxes, because she’s just like me.

Imagine, years later, a teacher finally listens. And you’re told that yes, your child has a thing, and then someone mentions gently – you do realise that you tick all the boxes for that thing, too?

Imagine having a job where you spend all day inside someone else’s head, using your powers of observation and your empathy – yes, empathy, the thing that you’re told you can’t have – to create stories which make people laugh and cry. Imagine being able to stand in front of huge groups of people at conferences and talk, and have people come up afterwards and say “thank you for making me feel like I could do it, too”.

Imagine if the payoff for doing those talks was reaching the end of the day so tired that the noises and the people and the chatter all blurred into one until you felt like you were inside a bell jar, mouthing hopelessly.

Imagine if, despite telling your daughter that she should be proud – fiercely proud – of who she is, of her sense of humour and her kindness and her passion and her loyalty and all the things that make her amazing, you were nervous of saying it out loud for yourself.

Imagine that.

I am a mother, I am a writer, I am a friend. I make people laugh. I am kind. I am compassionate. I am bright. I am creative. I am a lot of things.

I am autistic.

I wrote the above when I first received my diagnosis of autism. Three years on, I’ve written the book I wished I’d had as a teenager – one where I might recognise myself. I wrote it for anyone who ever felt like the world didn’t quite make sense.

The State of Grace is published by Macmillan Children’s Books on the 6th of April.

Whip-smart, hilarious and unapologetically honest, The State of Grace is a heart-warming story of one girl trying to work out where she fits in, and whether she even wants to.

A sweetly funny look at first love, family and faking it told from the perspective of a heroine with Asperger’s and her own particular way of looking at the world. (Red Magazine Online)

This brilliant coming of age novel for young adults is set to become a classic. (AGA Magazine)

Buy here:

Waterstones

Amazon UK

Hive

Book Depository (with free world wide delivery)