If we never hear from them again, then what was the point of Walter and Catherine's budding romance? So, her husband died, clearing the way for Walter to romance her, but then we never get to see what becomes of it.

And good grief, Lady Catherine seems to suffer from the same convenient short-term memory loss that Bella Swan does. "My husband just died? Oh, well, I've got a new, cute man to cheer me up. Oh, we're in danger? Now I'll remember my poor, dead husband. Walter's with me again? Ah, forget my husband!"