Dexter has always been manipulative; he has to be, to survive. But the levels we see him go to in this episode make me really uncomfortable. I think Dex has been a darker character this series, even though we haven't seen him kill nearly as much. It's been more who he's killed and the way he's covered it up. He's more sly. Not quite following the code. I find that more disturbing than when he drags his knife through another killer's cheek.
And it's interesting, because this is even almost stated in the show; "I take no pleasure in manipulating Miguel this way. Still, I think he'd prefer it to my usual alternative."
Dexter himself is uncomfortable with the measures he's taken. And they're seen as a viable alternative to murder; not less, just, different.
The ending? The way he's taken those words and used them? A mixture of endearing and creepy, heavy on the creepy side. The thing is, Dexter doesn't believe it, but... the way he protected Astor, for instance. The way he's protected Rita in the past. I think he does love them. I think he can't recognise that aspect within himself because he's so convinced he's a monster.
He is a monster.
Sometimes that's difficult to remember.
This seriously is one of the best television shows ever made.