Well, those marriage-therapy sessions on this week’s Dexter were almost as painful as enduring a seat on the analyst’s sofa yourself, didn’t you think? Oh, right: SPOILER ALERT: DON’T READ IF YOU HAVEN’T SEEN THIS WEEK’S EPISODE “IF I HAD A HAMMER.”Now: If I had a hammer, I’d have been tempted to use it to at least warn Rita not to ask me to go buy more bread or milk whenever she’s mad at me. Once we got into the therapist’s office (and didn’t Roma Maffia look positively relieved to be away from Nip/Tuck?), it only took a few sessions for needy Rita to realize (“Duh,” as everyone was saying this night) that it’s hard for Dex to talk about his feelings, and that he still needs some space. Literally. “I need space to keep my stuff.”

By the end of the hour, she was happily handing him a padlock for his newly built back-yard shed. To me, this stuff, plus the LaGuerta-Batista official break-up subplot, took up time I wanted to be spending with…

Trinity — or rather, Arthur Mitchell, family man, teacher, church deacon, all-around good guy with a freakish attachment to his dead relatives. He’s proving to be a beautifully well-rounded character, isn’t he? The scenes of Arthur singing in church, squeezing his wife’s hand affectionately, and helping to build houses for the needy played to the gentler side of John Lithgow, an actor who can fine-tune the intelligence he radiates to portray suburban satisfaction.

That old theme — villain is the flip side of hero — is given a nice fresh twist in Dexter. That’s because Dexter is, all by himself, both hero and villain. So to have him encounter a man who’s done the Two-Face thing in some ways even more successfully than Dex, well, that’s unnerving for him, and thrilling for us.

And besides, the real core of this series isn’t death or crime, but the keeping of secrets — that’s what we identify with most intensely in Dexter Morgan. If we, like Dexter, are forced to acknowledge that there’s also a little Arthur “Trinity” Mitchell in us, that’s a dark place I want to keep exploring each week, don’t you?

By the way, a number of you Commenters were right when you wrote saying I should have given Jennifer Carpenter a lot of praise last week for her strikingly emotional acting in the parking lot where Lundy’s body had lain. Her distraught cry to her brother — “I’m broken!” — not only shook Dexter to his core, but also shook us as well. It was a great performance.

All the more reason, therefore, to see this week the way Deb has been brought back into danger as she pursues a clever but erroneous theory about who killed Lundy. As Dexter said in voiceover, now he has to worry about Deb coming into Trinity’s deadly view.

Did you watch Dexter this week? What did you think?