I think this song is about a relationship between two people coming to an end. He's singing about how it was a good relationship while it lasted and even though it is coming to an end, let's have one last good time together hence 'the show it can't go on'. He is comparing his relationship ending to the end of a show.
I think this song is about a relationship between two people coming to an end. He's singing about how it was a good relationship while it lasted and even though it is coming to an end, let's have one last good time together hence 'the show it can't go on'. He is comparing his relationship ending to the end of a show.