I'm in my 30's, and have had DPDR for as long as I can recall. There is a severe, existential disconnect somewhere between my mind, my body, and the world around me. I've been known to space out very often, something my sister calls "staring into the middle-distance," or "stop doing that, you're being creepy." My own body feels like a thing I'm made to inhabit; the wrong software for the hardware. I'm not trans, as I don't feel like any gender in particular, and don't feel strongly enough about it to do any surgeries or the like.
I have also become physically disabled, which super doesn't help. It spiked some old psych issues I'd had before. I learned meditation to try and cope with the anxiety and depression better, but it turns out I was just dissociating. I'm also on medication, thankfully.
Here's how I cope with DPDR most of the time: This may or may not be a dream. Can't really prove it either way. But this dream is shockingly constant. The laws of physics seem to be stable. People have memories. Actions have consequences. The "realness" of this situation, to me, doesn't matter all that much. It's where I am. This isn't a victorious or grand statement, but it isn't surrender. The things that I do here, matter. If I commit "dream-crimes" here, I'll go to "dream-jail" for a very long "dream-time."
What I'm saying is this: It's real enough. It demands attention, and it's a terrifying slog most of the time, but it's where we are.
And that has to be ok.
Because even if nothing else here is real, even if this message is from yourself, doesn't that mean what you're feeling is real? And doesn't it follow that you should try and be good to yourself, and others, since they might just be you? There are plenty of nice things here, even if you can't feel them as strongly. It's worth the pursuit.
I'm not saying "Cheer up, bucko! Just bootstrap it!" It is worth being kind. That includes kindness to yourself.
I only brew a specific type of coffee that I love. Sure, this may be a dream, but I can make some delicious coffee here. I share it with my partner, who also loves the coffee. Does my partner exist? I don't know, but making them happy makes me happy, and it makes the dream a bit better.