Explain the ambiguity of the nunnery scene.

I suppose we wonder about Hamlet's actual motives in this scene. He is supposed to be acting "crazy" yet he is quite vicious towards Ophelia . Instead of merely acting bizarre, Hamlet crosses the line into personal attacks and slander. Hamlet, for example, accuses Ophelia of having relationships with other men,

That if you be honest and fair, your honesty should admit no discourse to your beauty.