Note: The "glory" of the title is ironic.
This is a very swift moving, lean play, which may be about ignorance, learning to pay attention to yourself, female subservience, psychopathic love or even the mental effect of poverty and absent family life on a young mind. The play is so efficient and flexible though that if I kept considering themes, several more are there. Because of that flixibility of theme, that encompasses many issues, The Glory of Living is an excellent play.
It reminded me of some of Sam Shepard's plays about poor, down and out, violent and seemingly foolish people. It also reminded me of Badlands, the 1973 film about the young, beautiful couple who murdered several people.
Another review here spoke of the simplicity with which Gilman deals with heavy subjects, allowing the audience or reader to contemplate and feel the issue out, so as to see the people involved and not be lead by spectacle and judgement. That is a point I'd say is right on, because by the end of the play I was moved by the tragedy of Lisa.
Carl: (shaking his head) I can't even begin to understand you.
Lisa: Yeah. But I appreciate that you try.