May have spoilers if you didnt watch to the end! 
If you feel betrayed and cheated - surprise MFK! - you were betrayed and cheated by
Hanna Mackay - thats EXACTLY how Dexter was feeling at the end!! You
were right!! Thats what makes the end genius - disappointment!!
Yes i felt at the end also what the cooking cook, what is that??!! I
didn't sleep all night and day trying to find explanation, because it
was shocking exactly by all reasons how are described by people who
gave 0 point in review!! And i found it!
Who was real Dexter whom we followed so much time and loved? He was
serial killer that we all know his nature! What was the main "song"
that started with irritating seasons 7-8? That he doesn't want to kill
anymore because of Hanna, he wants to be with her, etc. even his father
says at the end, you are not old Dexter anymore. He stopped to be
himself and this delusion came to him from Hanna! Basically, that was
AGAINST his nature, surprise, but Hanna was exactly who brought him
against himself! In this story Hanna is not a positive character, she
is exactly his enemy! I hated Hanna, i knew it inside, and even if you
loved her, thats has explanation too. You were LOYAL with Dexter.
Loyalty is when you believe to somebody about good or bad as a given,
without doubts if they are right or wrong. Those who hated her were
loyal with Debra, she was inseparable part of Dexter.
Hanna actually was never presented as a positive character. She was
from beginning negative. If you read about narrative theory and means
to present characters, you will learn a few interesting things how
author or director develops the story and by which means. Hanna was
never presented positive. Therer is not a single action from director
about this. The biggest cheat starts from her appearance. Previous
women were classically blond if they were good, kind looking, sweet, or
black bad like Lila with many supporting details. And here the first
delusion comes - Hanna is blond, supposed to be good, but empty of any
other proof about this. She is not exactly sweet, the actress was
chosen to show her, is someone from whom men loose head, model looking,
drilling eyes, very stressed lips when she talks same all the time.
Blond but not good.
In narrative the author maybe of 2 types: the
audience see story only through his eyes, and the omni-present author
(who sees everything). Here is a mix. Dexter is the first type,
everything else is the second type. And now notice, that Hanna was
never shown to us from the eyes of omnipresent author. Everybody else
were shown sometimes alone, out of Dexter vision, we could see how they
reflect about their actions, their thought, regrets, worries, joys.
Hanna - never. She was NEVER shown alone with her thoughts, actions.
Only through Dexters eyes, she was only his own delusion of real
himself!! NEXT cheat how they met. She was already under crime
investigation! Director shows us only how she drills Dexter with her
eyes to seduce him, thats clear in every scene. Of course! On him is
her future, he rules the evidence! There could be no other solution!
Doubt? You think the rich guy with yacht appeared out of nothing later? Same
story! She needed to survive, how she explains all her crimes, she
needs to be protected!! The only reason of any her cold action! Only to
escape investigation, then prison, then being caught. You think it took
her much time to turn Harrison into love to her?:)
She was always given to this movie as a negative, which means enemy to
Dexter and this is who she was to be! He acts according to this not
real himself and doesn't kill Saxon and result is vegetable state of
Debora! He took decision and understood exactly that moment. She is his
inseparable part! Look second time last episode, everything is there!
Later he tells him in police camera, you helped me to see who i really
am, cut pieces and blood! When Debora becomes vegetable, it strikes him
and he hates this himself whom he turned to be because of Hanna!
Basically he hates Hanna at that moment! You feel cooked up because you
feel exactly how he feels at that moment!! He is not gonna be with that
woman never! Look how he talks on phone last time. To Hanna very cold,
only where are you? and words of love only to Harrison!
So, congratulations, you felt exactly right being pissed by the end,
because you felt Dexter and it means you really watched and your love to
him is not ruined!
Woahh and her last phrase to Harrison? Lets go eat an ice-cream?;)
Thats the genius peak of her expression as a negative character!! When
else Hanna offered somebody to eat unless it aimed at getting rid of
unnecessary ballast, especially that she didn't need him anymore after
escaping from USA?;)
