Artists Need to be Passionate
Have you noticed that the most important message of Scorsese's episode, "Life Lessons", is that artists cannot have average, simple, balanced lives? According to the story, artists need strong emotions, they need to be passionate otherwise they become mediocre and can't create great works of art. Nick Nolte's character forces himself to be in love with the assistant; he doesn't actually love her, but he needs to be passionate, he needs to feel love or pain or anger or lust all the time and very intensely, otherwise he can't create! He feeds on her emotions.
Billy