My sister and I shared a room for most of our life. She grinds her teeth. If I'm asleep, I can't hear her and I'm fine. If I'm awake, I just cannot get to sleep. I lie awake, tense, waiting, hoping that she's done and that she'll roll over and
stop doing it. But then she'll do it again, and internally I'm SCREAMING. My fists are tightly clenched, my pillow will be smashed into my ear, I'll hope she's done, and *krtch krtch krtch* she'll do it again. I don't know how it gets through the pillow. It just does.
We bought a sound machine, but it only works a little. I found that listening to music (loudly) helps a little.
It goes up my spine like nails on a chalkboard. Imagine if someone had a chalkboard and, as you were trying to fall asleep, would grate their nails on it every couple of minutes.
Fortunately, now we have separate rooms

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