If I were scouting locations for my nightmares, I’m pretty sure a fluorescent-lit cubicle with multiple mirrors and me standing in the middle, shivering in my underpants, would be an excellent choice. I am the opposite of a clothes horse. (What is that? A clothes pedestrian?)

My wardrobe was of not even fleeting concern when my husband, 16-year-old son and I decided to leave Albuquerque, New Mexico, and move to Amsterdam in the winter of 2012. We were looking for change and adventure, so we got rid of most of our stuff and moved, taking 38 boxes and three cats. I had travelled abroad before and knew that my size would be an issue. I am an American size 20 (UK 24), also known as “plus size” or even “women’s size”, both vague and euphemistic ways of saying fat. In one shop, I fitted a size 20 on the bottom and 22 on the top. “Plus size” implies that there is some platonic ideal size out there, and that I was beyond it. “Women’s size” implies that fat women are women and that other women are... not?

So I stocked up on clothes for all of my family before we departed, buying new jeans, underwear and pyjamas at my favourite, reliable superstore: Target. I couldn’t have imagined, though, when we arrived in Holland, how little choice there would be in our sizes. The shops themselves were tiny (and very specialised), and I didn’t have the vocabulary to ask where to go for what I needed.

The Dutch shop assistants also tended to be very frank and would say, 'You must be here to buy a gift for someone else'

I was also embarrassed by my weight, and felt conspicuous, like the only fat person in the country. It wasn’t the first time I had felt fat, but it was the first time I felt that everyone else was thin the Dutch are almost uniformly tall and slender, and there was absolutely nothing in my size. The Dutch shop assistants also tended to be very frank and would say, “You must be here to buy a gift for someone else” or, “You must eat a lot to be so big.” I always said that if I ever saw a larger woman in the street, I would stop her and ask, “Hey girl, where do you shop?” But I never saw one.

I’m not unaware of the space that I take up in the world (and were I ever to forget about it, there is always someone ready to remind me). People seem to enjoy telling me that “obesity is the most dangerous health risk”, but they say it in a way that makes it clear this is not really about my health. It’s a way of saying: “You’re disgusting. Put down your fork.”

It is exhausting to feel as if your value to society is less the more you weigh

I understand the health risks of being big. I have lost and gained weight on many occasions, and I support anyone who wants to improve her health. But it is exhausting to feel as if your value to society is less the more you weigh, and I am tired of having to defend my body to strangers. I would simply like to be able to buy clothes to wear while I go about my everyday life.

After our stint in Holland, we decided to relocate to Scotland, where my son was going to university. Before the move, we had a brief trip to the States, and I drove my rental car to Target as soon as the jetlag wore off. Target has everything from clothing to car accessories, and sometimes a full-sized grocery store. I have always enjoyed slipping clothes shopping into other errands, picking up a latte at the in-house Starbucks and filling up my red cart. This time, I piled it high with all the things I thought I might need in my new country (and which I had had to live without for so long).

In the US, large-size clothes are often in a separate department, or there are shops that sell only clothes for larger women, such as Avenue and Lane Bryant. (Lane Bryant has more than 800 stores in 48 of the 50 states. Some people love them, and then there’s a friend of mine who calls them “Lame Giant”.) Sometimes, this division into larger and smaller seems like a big-girl ghetto; sometimes, it’s nice not to have to move through rack after rack of clothes that were not made for me.

A lifetime of trial and error has taught me a few things. I know that a store such as Gap might stock a couple of larger-size items, but Banana Republic, for instance, will label a shirt that is no larger than a medium “One Size” and call it a day (though many shops offer larger sizes online). Occasionally, I’d try some place new, but mostly I found it easier to stick to places I knew I liked and had things for me (hence my devotion to Target).

Two years since arriving in Scotland, life suits us much better than Amsterdam. The people are friendly. We don’t own a car, and because Edinburgh is such a pedestrian city, it’s easy for us to get our 10,000 steps a day. I run a reading and writing class, my husband can walk to his job, and my son isn’t far from his university.

‘We search the racks and stacks for anything in size 22-24.’ Photograph: Alamy Stock Photo

But my jeans are wearing out, in that particular way that larger girls know to dread. All the walking has turned the exact spot where my thighs touch into a threadbare cobweb of denim. (Designers of the world, I implore you: apply your ingenuity to this issue.) The haul of clothes I bought two years ago isn’t going to last much longer, so last month I decided to brave the British high street for the very first time.

Before I hit the shops, I enlist help from two writing friends (neither of them as large as me, but not size XXS, either). Siobhan is a gorgeous, stylish Edinburgher who usually turns to vintage-style clothes to express herself. Felicity is newly moved back to Glasgow, where she went to uni, and wears an eclectic mix of sparkles and bold patterns with edgy leather boots and jacket, and, it turns out, sews many of her own clothes because she has the taste and talent (plus they fit better).

On a rainy morning, we head for Princes Street in Edinburgh, armed with a website showing American to British size conversions. My expectations are low; the only goal I have is to leave with a pair of jeans, and I’ve set myself a budget of £100 for the entire trip.

We stop in at Urban Outfitters, where I am by far the oldest person in the room. The woman I ask for larger sizes whispers into a microphone at her ear, like a secret service agent, before shaking her head at me – there are seemingly no words for her to express sizes bigger than large.

At John Lewis we walk through museum-like exhibits of clothes in every style, each one offering a woman a different way to be. I name them as I browse: Mother-of-the-Bride Every Day; Bohemian Rebel; Downton Abbey 2017. There are T-shirts that cost more than £100 and jeans that have been artfully distressed, as if for a Hollywood actor. Felicity asks a woman briskly folding things where to find plus sizes. She says there aren’t any sizes that big in the shop at all. We go to the haberdashery department, where Felicity helps me choose some gorgeous fabric, promising to make me a dress herself.

My mother shopped at Catherine’s Stout Shop – not exactly designed to build her self-esteem

Having endured my rhapsodic description of Target shopping, the girls suggest that Marks & Spencer might be a good bet. We search the racks and stacks for anything in size 22-24 but find nothing at all. A gaggle of women dressed in M&S smocks are very friendly but merely wave vaguely in the direction of the clothes, telling me that there are “sizes out there”. They add that they can order anything in, which is helpful, but I really need to try something on. We return to the racks of jeans. I can’t find anything larger than an 18, so I decide to try them on, to estimate (by how high I can pull them up my legs) which size to order. I take two pairs: one regular, one “relaxed” and both “ankle-grazing” length (since jeans in my size tend to be designed for a woman approximately two feet taller than me). Siobhan chooses a patterned, geometric skirt and a shirt dress, and Felicity a sweater and slinky, sparkly dress. We head for the dreaded changing rooms.

Most of the women I consulted for advice before this shopping trip (friends and Twitter followers) avoid changing rooms altogether, preferring to shop online. Most sites for larger sizes go up to at least a British size 32, and there is a lot more variety. They tell me about Evans (the closest to a British equivalent of Lane Bryant), Asos Curve, Marisota, Curvissa, SimplyBe, Yours Clothing and lots more.

🌸 Me blowing flower petals over anyone who says that people shouldn't love their belly rolls 🌸 😏💜💙💚🌈🌞 Photography by @beckylongphotography for @_thebeautyofimperfection project! ✨ A post shared by Megan Jayne Crabbe 🐼 (@bodyposipanda) on Feb 6, 2017 at 12:15pm PST

Meanwhile, social media has done its bit to show that there are many ways to be bigger and fashionable. The growing body-positive movement has Instagram stars such as @bodyposipanda, who posts untouched images of herself, belly rolls and all; and Jessamyn Stanley, a yoga instructor who demonstrates that you can be large and athletic. Nike are now getting in on the act, launching a plus size line (finally). How things have changed. I remember my mother shopping at the one store in town that had big clothes in the early 1980s, and it was called Catherine’s Stout Shop – not exactly designed to build her self-esteem.

Lately, I have been engaging in some body positivity myself. I’ve made the decision to stop listening to other people’s judgments. In Holland, where people were most cruel (and that’s saying something, because I went to high school in America), I began to interrupt any nasty comments with, “Don’t talk to me.” Now I try to say that again to anyone who wants to control me by judging my body (even myself).

***

Back behind the closed door of the M&S changing room, in my own personal nightmare, I undress, trying to avoid eye contact with myself. Swiftly, with the deliberate movements of a condemned woman, I pull on the “relaxed” pair, expecting to hit a roadblock at my hips; but to my surprise, they slip up and zip. The hem of the jeans is at my ankle. What sorcery is this?

I slip the jacket on to my shoulders. It is well-fitted and the sleeves come to my wrist. I look awesome

I step out of the cubicle to where Siobhan is modelling a shirt dress that is miles too long. I ask Felicity how her dress was. “Ugh!” she says, showing me where it is unflatteringly baggy, and where a tuck here and a dart there would make a huge difference.

Then they turn to me. Their discerning eyes take in the fit of the jeans and suggest that I go back in and take the plunge, trying on the “unrelaxed” pair. Even I could tell these fitted me better (and, at £25, they are well within budget, too). Flushed with success, I longingly touch the cuff on a leather jacket.

“Do you like that?” Siobhan asks.

“Yes, but… I don’t think I’m that cool.”

“Try it on!”

I slip the jacket off the hanger and on to my shoulders. It is well-fitted and the sleeves come to my wrist (the same Amazonian woman who usually wears my size jeans usually also has very long arms). And here’s the thing: I look awesome.

Suddenly, in the new jeans and leather jacket, I get some sense of what my thinner friends must often feel – where the fun of shopping comes from looking at something on the rack and transferring some of what makes it cool to themselves. For me, it was a splurge at £55, but what I leave with is so much more that just an outfit

How to shop big

1 Don’t forget the basics. If your bra fits properly, then everything else will look better (try Freya and Panache).

2 Size is a number, not a moral judgment. That number is based on the block (the model used to make patterns).

3 Take a friend with you for a second opinion.

4 Online shopping takes away the fitting room nightmare (but you do need some idea of size to start from, so take measurements).

5 Big doesn’t mean boring. Try Boohoo, Lindy Bop, SimplyBe, Asos Curve and Collectif.

6 When you find your size in each store, make a note of it, so you are confident ordering online.

7 Don’t buy things that aren’t your size or style, “for when I lose weight”. Shop for what makes you look and feel good right now.