scorsese deliberately packaged the final scene as an ambiguous ending, and the key word is "packaged" because it was only made to seem like you could even choose between two endings.....but nope, there's only one true ending and the brilliant storytelling just leaves no argument on that case.
how Shutter Island managed to put me directly in Teddy/Andrew's exact state of mind at that moment of realization was really smart and frightening and I could feel what a delusional mental patient would have felt like right until the ending. it made me doubt my real life for a minute because I realized that it could be happening to me too, I could be unknowingly living a life of lies, and it's because Leo perfectly portrayed Andrew's fear and emotions realistically.
the uncomfortable feeling of insanity and events which did not make sense from the middle of the film already hinted that something wasn't right at all, and it was hella uncomfortable and worrying indeed, like I didn't know if my mind was in the right place, if I was drifting further from the film. the final act completely threw me off. I was so glad it did how it did.
as much as I wished that Andrew could eventually be cured, the poignant result of how he chose his own end tied up Shutter Island with a perfect bow.
