When I have big events coming up, like a birthday party or a girl's weekend road trip or a vacation, I get so excited in the days leading up to that event that I feel like I may explode. Then when the actual event arrives, I find myself getting sadder and sadder for every hour that ticks off the clock. I spend the entire day/weekend/week thinking about how much time I have left with my friends, how much longer I have left at this party, how many days until I have to leave the beach or leave…