Psychological Projections...

Ophelia:

Ophelia's role as a psychological projection in the play is somewhat different than the other characters', as she seems to be a manifestation not of Hamlet's inner state but of his mother's.  Gertrude's character maintains an outward appearance of calmness and control, despite (as old Hamlet's ghost describes) the "thorns that in her bosom lodge to prick and sting her"(1.4.87-8).   Ophelia, on the other hand, has no connection with the poisonous mess of murder and incest that plagues Gertrude, other than through her connection with Hamlet.  It seems to be the murder of her father, by Hamlet, that draws her into the madness of the play. 

When Gertrude learns of Ophelia's madness in act 4, scene 5, her initial refusal to speak with Ophelia seems strange.  Her motivations for this avoidance are somewhat clarified, though, in the aside that follows: "To my sick soul, as sin's true nature is, ... so full of artless jealousy is guilt, it spills itself in fearing to be spilt"(16-20).  It is possible that Gertrude's guilt is a product of her indirect role in Polonious' death, although her previous lack of sadness about this event makes it more likely that she feels guilty for other reasons.  Perhaps she fears that an encounter with Ophelia will show her a mirror of her own soul/psyche.   This is exactly what Hamlet had threatened his mother with in the previous scene in her closet: "you go not till I set you up a glass where you may see the inmost part of you"(3.3.19-20).  Interestingly, Hamlet's next action is to kill Polonious, thus transforming Ophelia into a mirror of Gertrude's "inmost part".

Poor Ophelia...