Today in chorus, my teacher was talking about taking a song that we knew very well and looking at it with a fresh pair of eyes. Singing it in a different way, looking at the words and the music differently. And while discussing this, he made an analogy that caught in my mind. He said something along the lines of: "You don't look at your parents the same way you did when you were six, because you've changed."
This is an idea that I suppose I already knew, almost by default, but a concept that I'd never truly thought about. People change because we change. We change and we see things differently, and those people become different to us.