What do you mean by "1997"?

This is the lyrics from Sister Liu. It means to meet life and death for a hundred years. But whoever dies first must wait at Naiheqiao. By the year 100, the other one will die, and then we will cross the Naihe Bridge and take care of his life together. So it means to meet in the afterlife. There is a Meng Po on Naihe Bridge. She will give everyone who crosses the bridge a bowl of "Meng Po Tang". Everyone who drinks it will forget the past life. Maybe I'm afraid of forgetting each other and waiting to cross the bridge together.