Extremely frustrated with the lack of empathy and support

I'm 20 F and think I have SPD. I can't stand certain tastes. My sense of smell is very strong, I can smell my suitemates using listerine through a closed bathroom door. I have issues with sound (particularly human sounds like sniffling, coughing, loud talking, etc.) and rely on brown noise altered with a low pass filter to help me cope when I'm in crowded public places or when my roommate is having allergies. Stuff like that.

But the biggest problem for me is my sense of touch and response to pain. Always been terrified of pain and uncomfortable sensations, especially puking. Can't stand being barefoot. Can't stand having my feet touched. Can't sleep if the fabric of my sheets isn't the right texture, if there are crumbs in the bed, or if the fabric is pilling (but ironically, sleeping on a towel is helping.) Hate wearing anything with layers - underwear plus clothing is hard enough, add linings and pockets and it gets to be overwhelming. Never liked wearing jeans - I was able to for a short time as a teenager, but I can't anymore. I can barely make myself wear underwear most of the time. If I do, their texture and shape has to match perfectly with my pants. Pants are their own issue. It's extremely hard for me to find comfortable pants that don't look like pajamas. I hate layering my shirts. Bra plus cami plus shirt is too much. Can't stand it if my fabric clings in a certain way.

I'm struggling a lot because there isn't a lot of support for adults with SPD. Most of the support is for parents of children with SPD, but what happens when these children grow up? I want to know how to function in the real world but there are no resources available to me. I don't know where to look for professional clothes that I can actually wear, I don't know where to find underwear that don't make me want to bash my head against a wall. And it's worse because I can't explain it to people. They think I'm being petty or I could just learn to ignore it if I really wanted to. Or they think it's a psychological disorder that can be cured with some anti-depressants. I'm not lazy, I'm not picky, I'm not looking for attention. I've been this way for as long as I can remember. I just wish more people understood, and I wish I knew what to do and how to get by in the world.