my sister had ptsd symptoms so acute for a couple years when her meds were constantly being interrupted that she was unable to be vulnerable enough to fully undress for a bath, let alone be under running water where she couldn't hear if someone walked up on her.
i was homeless for a year, couch surfing and living out of my car and camping in a tent. sometimes facilities don't feel safe. sometimes there's no way to secure what few possessions you have. sometimes you just don't want to add to the burden of someone generous enough to let you drop a bedroll in their basement for a few nights.
wet wipes and bird baths only carry you so far, after a while you give up on the idea of ever feeling clean, and you just make sure you don't stink. you can keep up the mask for a little longer just so long as you don't ever wrinkle a nose. because you wouldn't have assumed we had those struggles to look at us, but as soon as the straights can smell you, you become that kind of mentally ill, that kind of homeless — the kind with less humanity than theirs, the kind that's safe to ignore.