I did try and put a spoiler warning before the post.
I am sorry.
Anyway my post just had an analogy type quote which illustrated how the ending is open to multiple interpretations and how everyone seems to have vastly different reactions towards the ending.
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Dexter lost me from Season 1 only. It was a good show but it was dealing with Anti Social Personality Disorder and his father (Harry) was a dumass, he was not helping the kid (Dexter). He was reinforcing his condition, and that is just stupid. Nonsensically. While their is no cure for ASPD, a therapist can make a patients lack of empathy, socially manageable.
And the thing that just blew away my suspension of disbelief was the Season 1 finale. Why would Harry adopt one brother and dump the other one in an institution. Why don't psychological institutions work in this show?
So I learned fairly early on, not to take this show seriously and always expect a shitty finale and a Season premiere that would obliterate any continuity with the previous season. That said, some seasons did perform better than my expectation like the preceding one.