These things hit you hard. Your first reaction is to feel sad, even a little depressed. But, I'm not sure if it's selfish, but they also make you more appreciative. Appreciative of your short time here on earth, of your loved ones and for all the little tiny life moments (and seconds) that accumulate to one big incredible experience.
This past week, I saw a status on Facebook that said, "....is amazed at how quickly happy thoughts fade. Man it takes work to be happy, I mean really happy." That one comment didn't just make me sad for that person, it actually kind of pissed me off. I couldn't disagree more. What I do think takes a lot of work is being miserable. Being happy is the easiest thing any of us can be - simply look around at the beauty. Plain, simple beauty.
It's these big, heart-hitting moments that make me stop and make me thankful for life.