If will follow you for 1000 miles but not miss home. It desires neither food nor flowers. It fears not water, fire, knives, nor soldiers. But it disappears when the sun sets behind the western mountains. Who Am I?
Sometimes I am loved, usually by the young. Other times I am dreaded, mostly by the old ones. I am hard to remember, also hard to forget. And yet if you do, You'll make someone upset. I occur every day everyone has to face me. Even if you don't want it to happen; embrace me. What am I?