In act II of hamlet, what does the queen believe caused Hamlet to go insane

Unrequited love was the answer to Hamlets antic disposition and insane mind. When Hamlet felt rejection, he turned to the depths of his mind to justify his emotion. He admits that he did love Ophelia once but, then goes to deny his love ever existed when Ophelia says she believed he loved her. You should not have believed me, for virtue cannot so inoculate our old stock but we shall relish of it. I loved you not. As many men would do in present time, Hamlet did as well. He was upset over the rejection he felt and denied any feeling towards Ophelia. The built up madness and hurt inside Hamlet turned into rage and insanity. He dwelled on his feelings of hurt inside his mind and let them build up to a hurricane of emotions. (im not sure just have a look)