Worried about Maddie's Mom (Theory)

Similar to Maddie when Janet took her body over the course of 02x06 we see Sandra fall into a darker and darker place. I feel like by the end of the season Sandra is going to find herself in the hospital able to see Dave (Maddie's dad).

The writes and show runners don't bring things up for no reason. IMO there have been to many mentions of Dave this season for it to be a loose thread we don't get some answers to by the end of the season.