Whereas the bedroom is an epicenter of activity (many guests) in "The Professor Part I" of Tuesday with Morrie, the bedroom is indeed a sickroom, more connected with suffering and death in Part II.
Morrie's fears ("When you're in bed, you're dead") are realized when his ALS worsens and affects his speech and mobility. Morrie had managed to use his chairs as lecture pulpits to speak to Mitch and Ted Koppel in Part I, but in Part II Morrie must be bedridden. The transformation takes its effect on Mitch and Koppel, for they must do more of the talking, and they both realize that they have precious few moments left with Morrie.
The bed is a symbol of theros (death) in Part II, mainly because Morrie has lost his mobility, and he must be connected to machines (oxygen). So says Enotes:
Morrie is on oxygen by the time of the thirteenth Tuesday, and relates that he had had a very bad spell the night before. Thinking that his time had come, he discovers that he was ready, and at peace. He tells Mitch that as long as people love each other, they can die "without really going away." They live on in the hearts of those whom they love, because "death ends a life, not a relationship." By the fourteenth Tuesday, the end is very near for Morrie. When Mitch arrives, Morrie is in bed, and is almost too weak to speak. Mitch says good-bye, and is brought to tears as he kisses his dear friend. Morrie dies four days later, serenely, with his immediate family close by. Mitch is present when Morrie's ashes are laid in the ground, and he realizes, with quiet bemusement, that it is Tuesday.