Periodic movement is what we use to measure time, yes. But I can't imagine that time is simply a human abstraction. Just because there's nothing to measure time

Periodic movement is what we use to measure time, yes. But I can't imagine that time is simply a human abstraction. Just because there's nothing to measure time with doesn't mean time doesn't pass, right? My brain doesn't like the idea of time in the context of relativity. Just because the relative (nominal?) measure of time changes as the forces of the universe may or may not cause it to doesn't mean the absolute (real?) period I wait for the train every day changes. Just because the clock stands still while you're moving away from it at light speed doesn't mean "time" hasn't been spent moving away from it. (I use nominal and real because, oddly enough, economics is the closest thing I can relate this to.)