Hamlet Questions

1.) Is Hamlet really crazy?
I think Hamlet is not really crazy. I think he is just faking it since he is able to switch from being out of his mind (crazy) to being sane when he chooses.
2.) Why did Ophelia give back the token of love that Hamlet gave her?
She gave it back because he was treating her differently and doesn't really love her now that he "lost his mind" and he harrasses her.