I think this song has more than one meaning. Yes, we as the audience are watching her from behind the glass i.e. the TV and expecting to be entertained but she is also speaking to someone special in her life who is only viewing her from a distance. He is too far away to be able to feel her or be with her. He also knows more about her, about her weaknesses and laughs at her inadequacies but she just doesn't join in on the joke. She is struggling to keep herself together trying to make it now on her own. She has resigned herself to the fact that this is what she will be to him, a clown behind the glass.
I think this song has more than one meaning. Yes, we as the audience are watching her from behind the glass i.e. the TV and expecting to be entertained but she is also speaking to someone special in her life who is only viewing her from a distance. He is too far away to be able to feel her or be with her. He also knows more about her, about her weaknesses and laughs at her inadequacies but she just doesn't join in on the joke. She is struggling to keep herself together trying to make it now on her own. She has resigned herself to the fact that this is what she will be to him, a clown behind the glass.