This episode was great! All the way to the shocking ending, which was great but very much sad. Hate to see beautiful kind Rita go but I guess it for the best. I was getting used to Rita and the kids, and I feel next season may feel a little empty without them. Also I was very much hoping that she would completely know everything about Dexter. His childhood past, his demon and uncontrollable need to kill. Of course Dexter only kills people who needs to be killed and not the innocence and I feel that would have brought them closer together, because I knew it was that mystery about Dexter that intrigued her. Where the writers would go from there, I don't know. Another thing I would have like seen this season was agent Lundy hinting more on knowing what type of person Dexter was, in a good way. It was like Lundy kinda knew something because he was always asking Dexter for some advice. Like only Dexter would know. Oh well, I guess you can't kill everyone off who knows what Dexter is..and Lundy and Rita only got so close.
Trinity did not kill Rita. He didn't have enough time to do that. Anyone can see that the killing of Rita has something to do with Dexter childhood and the original killing of his mother. I personally believe it has to do with FBI Agent Davis. Davis and his crew came in and took over the Trinity case.
Even though Deb claims to know so little about Dexter past, I think she put it together and can paint the picture of to who Dexter truly is. Anyway, it will be interesting to see what the writers will come up with next season. Which will be a very dark one.