Everything comes to an end. Everything. Whether it is something you enjoy, despise, or feel entirely neutral about, nothing lasts forever. It's a very startling thought.
On one hand, it's comforting to know that the bad situations can only exist for so long. One day they'll be behind me; and, although I will have new struggles, at least it will not be the same ones forever.
More disappointing, though, is the thought that the good things will all eventually end as well. One day I will not frequent the same places I go now. I can accept that, even though it may be sad to look back. Friendships last longer than situations, but still after enough years even the strongest friendships come apart--whether by simply growing in separate directions, or huge fallouts, or ultimately death. I finally have some of the best people I've ever met as very close friends--people who are genuinely worth knowing and worth relying on.
It makes me afraid to blink. Days fly by, even months. If I stop paying attention for a second, I'm going to realize I'm ten or twenty years older, and all of this is gone. The moments most worth living, the ones that are the most memorable, are the ones that fly by the most quickly. Time to make every second count and enjoy it.