You can tell from the start that this was adapted from the stage. The dialogue--for the most part--has the same earnest theatrics as your average play, and honestly it works fairly well in a knock-off Tennessee Williams kind of way.
And the stage adaptation becomes even more evident when it shows itself to be a comedy tear-jerker.
And, as I said, that's fine. It has pro-talent and it's always nice to bring the stage into your living room from time to time.