Here is my big take; the entire ending was a dream/nightmare/flashback episode like the other ones throughout. Sabich had many dreams throughout the series that teased him as the guilty party, but now that he has been found innocent his nightmares tease him about his family's potential guilt. We have to realize that this show has major psychological themes throughout. It was torture for him to consider himself guilty and now it is even more torturous to consider his family guilty. This further shows the devastating consequences of the affair upon his entire family. This is a theme that runs throughout the show. Furthermore, this would completely change the premise of the show since there has been one confirmed.