It should probably be noted that the audience is not all in perfect agreement that Buffy is hiding her tears when Spike finally returns to Earth. The 'tear' in question is very unlike the big fat obvious tears that Jeanty draws when he wants to show a character getting emotional, and may in fact be nothing more than the corner of Buffy's eye. (Didn't someone ask Jane Espenson about Buffy crying in that story, and her response was basically "Huh?")