>To believe he was crazy the whole time is odd due to the fact
>that they would have had to coach these crazy people he
>interviewed to lie about Rachel, which is hard to believe, and
>also that the whole cave scene was in his head... The one clue
>you look back on is when Sheehan can't even get a gun out of
>it's holster, at that point it shouldve been clear he was not
>a marshall

I mean, they address that immediately afterward. He even knows they've been coached... he just doesn't know about what.

I do like the idea that some of it was real, and while he was crazy, he was onto certain things. The end shot of the lighthouse can absolutely be interpreted as an implication that they really do lobotomies there. I'd just need to see it again to look for hints as to what might be real, since most of it is obviously a fabrication.