I have nightmares because of trauma, so I take anti-nightmare medication. I don't really sleep either, so that's a good way to avoid them even though I had chronic insomnia. I don't know if it's common in ASD because in my case they're trauma related. I can't even visualise things in my mind (in the daytime, and seldom in dreams), so that makes it harder for me to see scary things. Somehow my trauma manages to break through that and I can see everything if I do have a nightmare.
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And in the end, the love you take is equal to the love you make.