From the movie "Shall We Dance?" on why people get married:
"Because we need a witness to our lives. There's a billion people on the planet. What does any one life really mean? In a marriage, you're promising to care about everything. The good things. The bad things. The terrible things. The mundane things. All of it. All the time. Every day. You're saying your life will not go unnoticed, because I will notice it. Your life will not go unwitnessed, because I will be your witness."