Before I was attacked, I would write about the future – just goals, lists and plans. I’d scribble without depth or substance about the things I wanted to do with my life, whether short or long-term, and how I thought my future would be: a successful career in TV and modelling, marriage, a family. I didn’t reflect so much as I did after the attack and still do now.”

Katie has found many reasons to be happy now – over lunch she shows us Instagram pictures of her wedding last November to her new husband, Richard, and while having her make-up done she regales us with anecdotes about her daughter Belle, who’s nearly two, and her sister Suzy, with whom she’s very close. She’s excited about her busy year ahead. She’s filmed a new series of her Channel 4 show, Bodyshockers, and a brand new show, Should Have Seen A Doctor, Should Have Seen A Dentist. Later, during our chat, her positivity doesn’t waver even when recounting her blackest moments. It’s hard not to be impressed by her relentless optimism.

“I call it ‘survivor’s speak’,” she tells me. “I live by positive quotes and affirmations. Things like, ‘You may be climbing a mountain right now but look at the view when you get to the top’. It might be an obvious quote, but it reminds you that whatever struggle you’re going through, there has to be an end to it. I’ve had to learn to think that way. Now, I refuse to believe there’s not a purpose to any struggle.”

But to say that her words have always been positive would be a grave understatement. In the immediate aftermath of the attack, Katie was left disorientated and unable to speak from her hospital bed. She wrote down her questions and thoughts to communicate with her distraught parents. “Am I dead?” one note asked. Another read, harrowingly, “Kill me.”

“In the months after the attack, I wrote a lot of dark things,” she says quietly. “Letters, angry thoughts. I kept them private. Ironically, it wasn’t the act of writing those things but later destroying them that I found most useful. When I read them back months or sometimes years later, I’ve felt ashamed of how I felt – of the words I put on the page.

“At the time I needed to offload my bad thoughts and feelings. But reading something back and not recognising yourself is hard. It’s like being filmed during an argument, when you say things you don’t necessarily mean that are hurtful or unkind, and then watching it back. I ripped up the thoughts I didn’t want to associate with myself any more – things that I wouldn’t want anyone else to read.”

What are the most difficult words she has put to paper? She replies without missing a beat: “My witness statement.”

In 2009, Katie’s attackers – Daniel Lynch, a man she had briefly been dating, and Stefan Sylvestre, who Lynch hired to carry out the attack – were each handed life sentences with the possibility of parole, with Lynch ordered to serve a minimum of 16 years. Sylvestre applied for parole last year but his application was denied. “After the attack, I started reading a lot – usually stories of survival from real people like Tulsi Vagjiani, who was burned in a plane crash,” says Katie. “I read anything which took away the feeling of isolation and used words, anywhere I could, to lift me.

“I used to write quotes or sayings on Post-it notes and put them around the house to remind me to feel better. I’d put them everywhere: on my bedside table for when I woke up, on the bathroom mirror, the cereal box, even the toilet lid. When I wrote my book of quotes – Start Your Day With Katie, one for every day of the year to help others stay positive – I went into my publisher with a shoe box full of all the Post-its I’d kept which I related to personally at the time. Now, the ones that resonate with me most are in the book of dates which shaped my life – my daughter’s birthday, my birthday, the day I was attacked and the day my attackers were finally dealt justice.”

I ask her if there are any words she hates being used to described her? “I don’t hate any words,” she says. “But sometimes I think words like ‘courageous’ and ‘inspirational’ are used too much in a gushy way. They lose meaning. It’s a funny label to call someone ‘brave’ because a lot of the time ‘brave’ isn’t a choice – it’s often the last option. I didn’t set out to be courageous, I just decided that I did not want to allow someone else to play god with my life. Why should they? I decided I needed to start again.”

Katie also uses words and aspirational quotes to help other burns survivors she works with via her charity, The Katie Piper Foundation, to stay positive, and says it has a great effect on their outlook. “Words are powerful,” she says, “they change how we feel. When people are unkind with words, when they label us, it can immediately change how you feel about yourself that day.

“We need to uplift each other and reject those labels, no matter what our story is. Positive words – writing and reading them – can make us feel more ambitious and able. They can make us happier.

“Writing, if not for anyone else to read, can help you gain a sense of having processed an emotion. It can release you from self-pity and help you move forward. Who doesn’t need that?”

As we conclude our chat, I realise there’s one word we keep coming back to which, more often than others, is fervently associated with Katie: beautiful. It’s how she admits she saw herself prior to the attack. It’s what the vitriolic Twitter users (who still troll her now) said had been permanently taken away from her that day. It was in the name of the 2009 Channel 4 documentary that made her a household name and catapulted her career, and is in the name of her first two books. Now, it’s also the name of her adored daughter, Belle.

“I chose the name carefully before I even met her,” Katie says. “It was sentimental – the French word for ‘beautiful’. I lived in France for a lot of my recovery and it became a special place for me. And I knew that Belle would bring beauty into my life and into my parents’ lives and replace bad images and bad memories of what happened to me with good ones.

“Even though Belle wasn’t here when I wrote it, my poem makes me think of her now, too. It reminds me of the sadness I feel that other people will never see the genetic resemblance between me and Belle – but I can see myself in her. And perhaps through her I’ll see something I thought I would never witness: how my old face would have grown with me and aged.”

“I refuse to believe there’s not a purpose to any struggle.” Katie Piper on the healing power of poetry and writing