I love that so much, like, she's fully taking responsibility not only for the Jenna Thing, and the Toby Thing, but she's also saying that Alison was part of her team -- that she was on Team Alison -- and that this is something that indicts all five of them, even unto Ali's actual death and all the fallout of that. It's one of the most stunning admissions/realizations any of these Little Liars has come to yet, and very satisfying. I don't believe particularly in penance -- because it can turn into addiction way fast and stops being about the Thing and starts being about your personal narrative surrounding the Thing -- but I do believe in redemption.
Spencer, coming off a long internal monologue: "What's it like to run away?"
Spencer tells him a story about how when she was about seven, she and Melissa were going at it and her parents, of course, took Melissa's side, so she packed a tuna salad sandwich and hit the road. She sat through Beauty & The Beast (she doesn't say it by name, but the timeframe and the parallels to the Spencer/Toby storyline make it pretty clear I think), ate her sandwich, got lonely and went home. Where, of course, nobody noticed she was gone. Toby asks sweetly that she talk to him first if she ever feels like doing that again, and then silently holds her hand. Spencer is having a fucking rough one, y'all.
Heading to the slasher-suspense thing this show does so well -- and so infrequently that it never loses its power -- Byron finds himself in Aria's room, being nosy. He picks up the Anderson book and flips through it... But doesn't look at the inscription. Ella finds him and starts up with him about not prying into Aria's life, considering she has explicitly asked that they give her some privacy right now, and things totally devolve into You Cheated On Me hell in about two seconds.
As usual, Ella is pretty much completely in the right, and Byron is doing his typical Willow Rosenberg crap of, "Why can't we all just pretend my terrible behavior never happened?" Which is, of course, the exact moment Mike comes upstairs and just shoots them a hateful look about how they need to stop jerking him around. Guess dinner's off.