Act 3, scene 1

I think that Ophelia is too obedient. And I'm not sure if she even loves Hamlet or not at all, because she didn't show any reaction whatsoever when Hamlet said he didn't love her in line 120. She is too much her father's puppet, and she has just about no free will. She doesn't think for herself, and in this scene it seems that this characteristic in her has developed even further.

Hamlet has become more unfeeling, and this is shown in his entire conversation with Ophelia. He is an emo prince bent on getting revenge, and doesn't care if it makes a monster out of him.

Polonius is just stupid. He's so obsessed with hating Hamlet and "protecting" his daughter, that he pretty much unknowingly gets caught up in the main plotline, about resolving the murder, and ends up on the murderor's side. Polonius is too narrow-minded, and doesn't notice what's actually going on around him.

I also think Hamlet is not crazy, but is just putting on an act to cover up any suspicious deeds because of what King Claudius says in lines 165-168: "Love? His affections do not that way tend; Nor what he spake, though it lacked form a little, Was not like madness. There's someting in his soul O'er which his melancholy sits on brood". I also noticed that Hamlet hints at his plans in lines 150-151: "Those that are married already -all but one- shall live." The one in "all but one" is obviously Claudius. I found it interesting that none of the characters caught that.