Dexter, Season 2

Lila:
I think you should give me another chance.

Dexter:
There's nothing you can do to help me. It's not even you. It's me. I am who I am, and nobody's gonna change that.

Lila:
Whatever you think you are - you don't have to be that.

Dexter:
That's where you're wrong.

Lila:
Stop judging yourself! There are no absolutes. No one's all good, or evil.

Dexter:
You're just gonna have to trust me on this.

Lila:
Jesus, Dexter, what are you so f***ing scared of!? You make yourself into a monster so you no longer bear responsibility for what you do! "Ah, I can't help it, I'm a monster," or, "Of course I was gonna do that - I'm a monster." It's sad! And it's pathetic! And it breaks my heart.

Dexter:
You don't think there are monsters in this world? You don't believe that people are evil?

[Lila shakes her head]

Dexter:
I'll show you evil.