Quite frankly, I wish those "Alli is so stupid!" people would disappear.
Because as hard as it is for these "saintly" people to understand, there are tons of people who go through what Alli's gone through, and it is possible for an intelligent person to make stupid choices.
Trust me, I'm one of those girls that abusive types steer clear of, because I don't have the personality traits they're looking for (i.e.I would kick their asses to Neptune).
I have a friend who was in an abusive relationship - as close as I was to her, and as much as I disliked her boyfriend (call it instinct), I could not convince her to ditch his sorry ass. She told me about the abuse gradually, but even then, it was only years later that she would finally get out, regardless of what I said.
I don't consider her to be stupid. I definitely got frustrated. But there is so much to consider in this kind of situation. He worked hard at isolating her, among other things.
Just try not to be an asshole when you consider this storyline of Alli's. Chances are, you don't get it yet, but I think you eventually will.