Maybe if I don't blink my eyes will tear up.
God, if I haven't thought that... I think half of Dexter's strength lies in the overlaps between Dexter's thoughts and ours. At one level -let's say, the comedic level- Dexter's alienation is but an exaggerated, self-consciously narrated version of some of ours. I can't count the times I've pretended to have fun at a party, or wistfully, if briefly, considered the comforts of loneliness...
But there's another level, of course. Dexter *is* a monster -an extraordinarily well-adjusted monster, considering- but a monster nonetheless (actually he's well-adjusted in a mimetic sense, I can think of other societies, none of them nice, were he wouldn't need to hide). That is the horror of it. He's not only fooling quite successfully his fictional peers, he sometimes almost fools *us*, with the big overlaps between his concerns and ours... sometimes masking the huge, seismic differences. Dexter is a trap at both levels, and while the Code of Harry is a wonderful device to try and keep him just this side of the identification line, it's merely a conventional device.
Dexter is a sociopath acting like a (tenuously) arguably good human being (for very Punisher-inspired meanings of "good").
He's a walking, monologuing Searle's Chinese Room. A machine -well, a broken human- implementing an algorithm (so are we all, at a certain level, but his program lacks that primate quality we all rely on for building a mutual epistemology of motivations). To watch and write him otherwise, to get trapped into his behavioral patterns, would be a mistake.
A fatal one.
PS: I'd really like to see the corner cases of his programming. From afar.
PS: Jesus H. Christ on a pogo stick, has anybody actually counted the number of samples in his little box of mementos?! I'll have to see how it compares to other serial killers, but that's a *freaking* lot.