Complex sentence: Hurley has not been taking his medication, is hallucinating his deceased friend Charlie Pace (Dominic Monaghan) and believes that the Oceanic Six have died and gone to heaven.
Split into simpler sentences: Hurley has not been taking his medication and suffering from hallucinations of his deceased friend, Charlie Pace (Dominic Monaghan). He believes that the Oceanic Six have died and gone to heaven.