At the ending of the movie Andrew talks to Chuck about how he thinks something 'bad' is going on on the Island, and he wants to leave it. He appears to be getting back in his old crazy character (Teddy), as explained in the previous scene ('like a tape').
This made me think he does not know he's fallen back into his old habits, and that he's crazy. Chuck notices this, and signs to the shrink that he's teddy again, and that he should get the lobotomy.
However when Andrew walks away he says the "die as a good person" line, which suggests he knows he's actually crazy, and thinks he should just die.
So which one is it, does he know he's crazy or doesn't he?