What does rachel tell heck about meeting someone? Its at the beginning of the movie

Rachel: "It's funny. I went around to say thanks for what she did at our wedding. You know when you've just met someone but straightaway you feel as if they're going to be your friend. Who knows why... Past life. Physiognomy. But for some reason you just kind of click. I don't know what I'm saying. But do you know what I mean?"