I heard the front door slam, the delivery guy speed off down the road.

‘Come on then, dig in!’ my boyfriend Paul said as he brought the massive Domino’s box into the lounge.

‘Oooh, don’t mind if I do!’ I said, lifting a couple of slices of stuffed crust onto my plate.

As we settled down in front of the TV, the pizza in grabbing distance along with a side of wedges and the remote, I couldn’t help smiling. Life was good. OK, so it wasn’t very exciting but I loved nights in snuggled up with Paul and a takeaway. Together three-and-a-half-years, we’d settled into a comfy routine.

I was 18 when we’d first got together. He was my first serious boyfriend and I worshiped him. A club DJ, he had loads of girls flocking round him. To be honest, I wasn’t quite sure what he saw in me.

At first, I worried about my looks. Would Paul find someone prettier, slimmer, sexier? But as the months grew into years and he became a permanent fixture at my flat, I started to relax a little.

Or to be honest, rather a lot. Whereas before, like most girls, I would go on the odd diet, slim into a certain dress for a special occasion, now I ate whatever – and however much – I wanted.

It was hard not to, really. Whether it was a nice meal out, a greasy kebab after Paul finished his set or a cosy night in with a bottle of a wine and a takeaway, our social life centered around food.

Slowly, my weight crept up…and up. But Paul was always telling me he preferred the fuller figure, that my womanly curves drove him wild, and I didn’t have to impress anyone else so I never worried about it.

But after three years together I’d gone from a curvy size 12 to a full-figured size 24 and 16-and-a-half stone.

Yep, there was no denying I was a big girl. But I was happy, and Paul obviously still found me attractive so what did it really matter? I told myself.

Only after four years together, my best friend – and Paul’s cousin – Amy dropped a bombshell.

‘Paul’s cheating on you,’ she told me. ‘He’s got some girl pregnant.’

To say I was shocked was an understatement

‘You’re lying!’ I screamed eventually. ‘You’re just jealous of our relationship.’

‘Why would I make it up?’ she reasoned.

But I wasn’t listening. I told her to get out and not to bother coming back.

Later that evening I confronted Paul.

‘It’s a load of rubbish, babe,’ he promised. ‘She’s never liked us being together but I never thought she’d stoop to this.’

The more I thought about the more it made sense.

‘He doesn’t do relationships,’ Amy had warned me when Paul and I had got together. ‘He likes playing the field.’

But flattered he fancied me, I didn’t listen then and I’d made the right decision so why should I take her word over his now?

So instead, I told Amy not to bother calling me again.

‘You do nothing happened, don’t you?’ Paul asked that evening as we shared a Chinese.

‘Course I do,’ I told him.

Still, I started to pay a little extra attention to his Facebook page.

Looking at it one evening, I noticed there were lots of women on there that I didn’t know.

‘It’s work, isn’t it?’ he said when I asked him about them. ‘They meet me once and then send me a friend request. Makes sense to keep ’em sweet. Part of the job.’

But logging on six weeks later I noticed another woman had tagged Paul in a photo captioned ‘my baby.’

I was so angry I didn’t think. I just posted a comment asking ‘Er, whose baby?!’

Minutes later, I received an inbox message from the other woman asking how I knew Paul.

‘I’m his girlfriend!’ I angrily tapped back.

‘So am I!’ the response said.

Silly cow, I thought. She probably just fancied him and was trying to stir things up.

But by the next morning, another eight women had contacted me all saying that they thought they were Paul’s girlfriends too.

They couldn’t all be lying…

I called Paul’s mobile.

‘This is your last chance to tell the truth,’ I told him. ‘Have you been cheating on me?’

‘Ok, I admit it,’ he said, leaving me reeling.

I called in sick to work the next day, just lay on my bed and cried. I felt like such a fool.

I dissected the last four years, remembered how secretive Paul could be – the mobile on silent, the text messages he deleted as soon as they came through, the nights he came home late, or not at all – had our whole relationship been a lie?

But there was an even bigger shock to come…

Later, when I’d calmed down I went back online to snoop on the Facebook pages of the girls who’d also been seeing Paul.

Most of them were open so I could see all their photographs and to my astonishment they were all really slim, a size 8-10.

It didn’t make sense because I knew Paul loved big women… Or at least that’s what he’d told me. Was that yet another lie?

I had the chance to ask him a few days later when he came round to pick up his stuff.

‘I used to prefer bigger girls but now I prefer skinny ones,’ he shrugged. ‘It’s not a big deal. Look at how you’ve changed since I met you – you used to be slim yourself.’

It was like a slap in the face. I felt sick. I’d spent the last four years scoffing my face thinking my size wasn’t a problem when all along Paul had obviously stopped fancying me.

I blamed myself for letting myself go. The guilt was crushing.

Even so, I vowed then and there that I’d lose the weight and show Paul just what he was missing. I didn’t think that he didn’t deserve me or wasn’t worth it, I just wanted to show him that I was just as good as those other girls.

I started straight away. I joined a gym and overhauled my diet. Before, I’d have a sausage and egg sandwich for breakfast followed by stacks of biscuits and a carton of fruit juice mid-morning before tucking into a
jacket potato piled with cheese and coleslaw for lunch, then chowing down on a takeaway or plate of pasta and cheese with bread and butter for dinner. As well as chocolate bars and packets of crisps as I watched TV in the evening.

Now though, I ate fruit for breakfast, a salad for lunch and chicken and vegetables for dinner. Snacks were out and I only drank water.

My stomach rumbled but the weight slid off. Every week the scales would be down by at least another four pounds.

‘You can’t keep this up, it’s too regimented,’ Mum worried.

But I was determined. Nothing was going to get in my way of winning Paul back.

Only as I began to shrink, a funny thing happened. Other men started to notice me. I got asked out on dates. And slowly, I began to realise. I didn’t want Paul back after all. I deserved – and could get – so much better.

Last Summer I finally reached my target – nine-and-a-half stone and a size 10.

A few weeks later I went to a party and Paul was there.

I was talking to his brother when he sidled over, introduced himself and began banging on about him being a DJ.

‘You don’t recognise me, do you?’ I asked him eventually.

‘Cassie!?’ he said, incredulously. ‘I can’t believe it’s you. You’ve lost so much weight. You look amazing! Are you seeing anyone?’ he continued. ‘Do you fancy going out for dinner one night?’

It was crazy. For ages I’d dreamed of him asking me out, me falling at his feet in adoration. But now?

‘Actually I am,’ I said. ‘And he’s a really nice guy. But I’m glad I ran in to you. If it wasn’t for you cheating on me I’d never have lost this weight and changed my life around. So thanks. You did me a favour.’

And with that I walked off, leaving him staring open-mouthed at my size-10 behind.

And now, a year on, life just keeps on getting better and better. I’m just about to go off traveling in America and Canada with Amy – yes, I apologised for not believing her and we’re best friends again. I’d never have had the confidence to do that before.

So looking back, I’m glad I found out my boyfriend was cheating on me. In fact, it was the best thing that’s ever happened to me. I doubt he can say the same!