XKCD shows you that someone else knows your life, that you're not alone in the world, that there are other people like you and your relationships. And it records this with stick figures, then alternately celebrates and makes fun of this.
Does it mean you're not alone, or does it mean maybe you're not the unique and beautiful snowflake you thought you were?
Katie seems to hate it for the same reason I love it.
http://xkcd.com/698/