The incident itself wasn't particularly hurtful or special.
I was still able to shop in the Thrifty Acres (my dad's name for Meijer) so I would've been in my early teens. My father, his girlfriend, her son, and my sister were waiting on me as I looked for some new clothes. I was in front of a mirror holding up a white shirt with a busy floral print. It was the only shirt in the entire women's department that fit. Believe me, I looked.
I was vacillating, because -- although I didn't know it at the time -- matronly is not my style. My father lost patience and told me it didn't matter if I liked the shirt or not; it was the only one that fit and was therefore the one I was getting.
Message received. Why bother with style when the grossness of my body overwhelms whatever puny statements I might make about who I am through my dress and comportment? It's a message that stuck so hard that to this day I have to remind myself to dress in clean clothes and shower daily. Who the hell cares if I spend any effort to look nice, smell sweet, or even be comfortable? I certainly didn't.
The insidious thing about the whole Fat People Must Dress Soberly In Clothes That Make Us Look Less Fat (And If That's Not Possible, To Make Us Look Like Nothing) concept is it hinders one's development as a person out amongst people. If one constantly wears clothing one can't relax and be themselves in, one is less likely to engage with the world around them. One is forever at a disadvantage; it's like trying to fight a war in spike heels, you're constantly off-balance.
And it isn't just fat people, it's fashion generally. We're all being told constantly what characteristics should be flaunted with abandon and which concealed in shame, and the specifics vary according to someone else's values or whims. I shouldn't wear this because I need to hide this pocket of fat, but I should because it has those gaps in the print that're so . . . something (honestly, I don't get that trend).
Wearing what you want, how you want, for reasons you choose -- that's a revolutionary act. There's a reason the unjust regimes in dystopian fiction have dress codes. Fat people get left out of the revolution because our choices are so limited, and based on the values of people who would rather we weren't visible. For my own mental health, I do what I can to buck that trend.
It shouldn't be this difficult. It's not like I'm challenging anyone's sensibilities. All I want is clothing that fits, is comfortable to wear, and suits my tastes. In a society that takes pride in its abundance of stuff, this should be easy no matter how far off the mold you are. Everyone has the right to take part in their own culture. As themselves.
Samurai Jack, season two, "Jack's Sandals"
examples; the caste-based color coding in Huxley's Brave New World and the Party's overalls in Orwell's 1984