Orsino and Olivia are worth discussing together, because they have similar personalities. Both claim to be buffeted by strong emotions, but both ultimately seem to be self-indulgent individuals who enjoy melodrama and self-involvement more than anything. When we first meet them, Orsino is pining away for love of Olivia, while Olivia pines away for her dead brother. They show no interest in relating to the outside world, preferring to lock themselves up with their sorrows and mope around their homes.
Viola’s arrival begins to break both characters out of their self-involved shells, but neither undergoes a clear-cut change. Orsino relates to Viola in a way that he never has to Olivia, diminishing his self-involvement and making him more likable. Yet he persists in his belief that he is in love with Olivia until the final scene, in spite of the fact that he never once speaks to her during the course of the play. Olivia, meanwhile, sets aside her grief when Viola (disguised as Cesario) comes to see her. But Olivia takes up her own fantasy of lovesickness, in which she pines away—with a self-indulgence that mirrors Orsino’s—for a man who is really a woman. Ultimately, Orsino and Olivia seem to be out of touch with real emotion, as demonstrated by the ease with which they shift their affections in the final scene—Orsino from Olivia to Viola, and Olivia from Cesario to Sebastian. The similarity between Orsino and Olivia does not diminish with the end of the play, since the audience realizes that by marrying Viola and Sebastian, respectively, Orsino and Olivia are essentially marrying female and male versions of the same person.