Zoe asks why he's doing this to her and continues to protest that Darius Rey killed her family. Dexter is officially taking her family-killing personally, for reasons Harry laid out earlier. He talks of the suffocating nature of family and finally gets her to admit it. "I couldn't breathe," she says...well, breathily. "You did it to survive," Dexter says, and whether that's faux-empathy or not depends on whether you actually buy that Dexter's gonna off Rita, Cody, and Astor this season. Which you don't. And neither do I. Which is part of the problem of this season-long arc so far, but I digress.
"What kind of father does this?" accuses Zoe, as she changes tactics. "What kind of husband?" "Not the kind who kills his family," says Dexter, as he slices into her cheek for his blood sample. I do like how this scene is playing out, Dexter getting more and more certain as he goes on that killing his family is not something he wants to do. He just wants to kill this woman for those sins. She tells him he's not going to be able to keep his double life forever. He's gonna have to choose, and he'll choose his life over theirs. "I won't," Dexter shoot back, his mouth going faster than his mind. "I'd rather risk them knowing the truth." There's a line in The Royal Tenenbaums where Royal tells his family the last six days he spent with them (during which time he conned them into thinking he was dying) have been the best six days of his whole life. And then the narrator (Alec Baldwin, of all wonderful things) adds: "Immediately after Royal said this, he realized it was true." That line was the first thing I thought of after Dexter said that. Accidental truth from a skilled liar. The admission kind of knocks the wind out of Dexter. He's almost in tears. "I don't want to lose them," he says, relieved that it's true. And with the strength of this newfound certainty, he stabs Zoe right in her heart.
Later, back at the bachelor pad, Dexter adds the newest slide to the box. Harry pesters Dexter with more doubts: Is he sure he doesn't really want to stay here, in solitude? Dexter seems sure. Harry then notes a dripping faucet and advises Dexter see to that. "You don't want this place going to hell. You need it too much." Dexter calls it his little vacation spot. Then he takes a call from Rita, who's on her way home early. "The house!" Harry panics. Dexter hustles off the phone, then races home to clean up all signs of a struggle. At home, he races through the cleanup process and is sweeping up the remnants of the mug as Rita and the kids walk in. He easily excuses the broken mug (he, um, dropped it), and Rita says the kids will be happy to make him a new one. Rita and Dexter collapse onto the couch, too tired to do anything but sit there. "I missed you," Rita tells him. "I missed you too," Dexter says. Glad he didn't let too much of that accidental truth-telling take hold.