[Marileangorifurnimaluim]

I think a point brought up in the article is completely accurate, and addresses the other question: why didn't Frodo go mad when the ring was destroyed? Because although he overcome by the ring, at the time of its destruction he had willingly relinguished it. This was demonstrated by the peace of mind he had once it was out of his hands (so to speak), and the fact he didn't even try to clutch after it as it fell.

Ultimately the quest not only succeeded on an external level - the ring was destroyed - but he won at the last the inner battle. That was the peace in his eyes. So the ring had no hold on Middle Earth even in its last bearer.

That it would take him long to recover is to be expected, but that peace and his final actions indicate the final outcome.

-Maril