I don’t remember a time when I didn’t feel fat. While I started piling on the pounds in my late teens, I was teased as young as eight for being chubby. The idea stuck. I remember overhearing my mum saying that she was worried I would get anorexia: I didn’t even know what that was. Suffice to say, I never did. I felt fat long before I truly had a fat body, but eventually the latter caught up with the former. I tried to diet on and off from my late teens to my late 30s, but nothing stuck. I was deeply, painfully unhappy.

I didn’t have a boyfriend throughout my 20s. Then, aged 30, I met my now ex-husband online, but that relationship was not without its complexities and I continued to gain weight. We got married in 2008. When we split up in 2013, I lost control and lived on junk food for a summer. I have always been an emotional eater and it was a vicious cycle. I was unhappy because I was fat, I ate because I was unhappy, then I gained weight because I ate.

Then I made a decision to save my own life. I went to my GP and, as always, they asked about my weight – at 162kg (25 and a half stone), I was morbidly obese. This time, the doctor suggested weight-loss surgery.

At first, I balked. I had never been to hospital for anything more serious than a broken bone, never stayed overnight or had surgery. At my weight, there were serious risks of complications and a small but real possibility I could die on the table. I remember walking down the street to work and stopping in my tracks at the thought of that.

But as I walked down the street I was in agony – a fact I never shared with anyone, although I suspect they knew. I couldn’t walk for more than a minute without being in extreme pain. My back would seize up and my shins would burn from the strain I was putting them under. I knew I had to do something.

So, in December 2013, I went to hospital for gastric sleeve surgery. This is where a large part of your stomach is cut away so you can eat only small portions before you get full. The surgery took four hours. Afterwards, I had to be woken every few hours and made to walk up and down the corridor because of the risk of deep vein thrombosis. The discomfort was bad for a week and I had a month of recovery before I could return to work.

People can be really weird about weight-loss surgery. Some think it is a “cheat”. Others think that I have wasted NHS money, despite the fact that I’ve probably saved them a fortune in treating the complications that might otherwise have arisen from my obesity. As a society, we make such moral judgments around weight gain and loss and the right and wrong ways of doing it. People treated me as a failure when I was fat despite my good job and life. People laud my weight loss when they see it, but there is sometimes a sense of disappointment in me when they realise it wasn’t done through what they determine as willpower.

But it was. The surgery is only the start. I have met people for whom it didn’t work; who cheated the surgery. Having the surgery doesn’t guarantee success – it gives you a head start. You still have to commit to your weight loss and work bloody hard at it.

That head start was what I needed. A chance to see a difference quickly and to turn my downward spiral into a positive feedback loop. One month after the surgery, I was walking for 30 minutes or more without pain. I now walk everywhere I can, trying to get at least 10,000 steps a day.

The stomach is a muscle, so after a while it stretches back to a normal size. I can now eat standard portions of food (although nothing like what I used to consume). I am not yet at my ideal weight and have joined Slimming World to get to my target, which is 16kg lighter than I am now.

I used to be a size 30; now I am a size 14. I used to loathe shopping; now I love it. The feeling of there being choices available to me that there never used to be is exhilarating. I used to avoid walking with others because the pain I was hiding made me quiet and unsocial; now I regularly tramp around the marshes near my home for miles with family and friends. Whereas I used to go home alone, now my life is, at times, full of dating and fun.

I have a confidence I never used to. I know things about me that were hidden under layers of fat and insecurity. I like my face now it has angles. I am even learning to like myself. It is hard and I don’t know if I will feel completely at ease with myself, even when I do achieve that final loss. But I no longer hate myself – and that is a powerful feeling.