Yes, the sentence is grammatically correct. It conveys the idea that while some people may be asleep, they are not truly resting because their minds are preoccupied with thoughts and worries about how to navigate the challenges of the following day.
Here are a few possible rephrasings:
1. "Some of us may fall asleep, yet we never truly rest, as our minds are occupied with thoughts about how to make it through the next day."
2. "While some of