Gotta say, I'm not a fan. Currently, only wear one if I'm wearing something see-through or some fancy dress, where a bra would give a "nicer" look, I guess. I find it physically restrictive and tiring.
As for measuring, you know, that was a mystery to me for a long time, as well. I look at some of my first bras now and wonder who the hell was buying those, as they're not the right fit in the slightest. Honestly, I mostly went by trial-and-error at the store directly. First time I measured (the right way...I think) was in lockdown, while shopping online.
I understand that very well.
As I teenager I went braless even when wearing my see-through tops, which the elders in my small village in Jamaica disapproved of.
My mum only instructed me to buy what she classed as way bigger than the sizes of herself and my sisters. Unfortunately, they were still way too small and could have caused me health woes.
When I lived overseas in Asia, I always received packages of bras from my best friend in the UK, because she knew I could not find my size. During lockdown I had an entire drawer full of bras that I'd stop wearing.
I'm like you, and wear them for the same reason you do now.
Whether it's to #FreeTheNipples, or just for #ASenseOfFreedom, I do hope that you will find comfort whenever you do wear one 💛