nostalgia or exhaustion

today i feel like i miss my youth.  i am remembering the crazy, fun times we had.  but now everything has changed.  is this what growing up/old is about?  cuz this sucks rocks.  some of my best friends are no longer around.  i feel abandoned.  left out.  this may just be the exhaustion talking.  i am so tired i feel like i could vomit.  everything hurts today.