On Pretty Little Liars Season 4, Episode 16 (“Close Encounters") Alison asked to meet with Emily — alone. Why? Well, in the meeting she claimed she couldn't trust the other Liars; it's unclear if she was talking about all three of them, or just Spencer and Aria, which is who Emily named before Ali broke in that she didn't trust them. Either way, that raises a big question: why?
Hopefully we'll learn more about Ali's distrust in the future, but until we get a solid answer, all we can do is speculate about her motivations. So speculate we will! We have a few theories about why Ali claims she can't trust the other Liars.
She's crazy paranoid. An obvious, though relatively uninteresting, answer is that Ali is just insanely paranoid and doesn't trust anyone, without actually having a specific reason not to. It's possible that she only reached out to Emily because she needed to talk to someone, and figured that Emily, who was once in love with her, was probably the safest best.
She's suspicious about their connection to "A" suspects. Both Spencer and Aria are closely connected to potential "A" suspects, and it's possible Ali doesn't want to give them more info about herself for that reason. Aria is dating Ezra. Spencer is a) dating Toby, and it's possible Ali doesn't know or believe that his "A" team dealings were actually for a good reason, and b) connected to Melissa and Wren, both of whom are highly suspect. This might even apply to Hanna, too, since she was once close to Mona.
Something about the night she disappeared. We still don't have the full story of the night Ali disappeared, and we know that Spencer, in particular, was out and about before the other Liars. Did something else go down between she and Ali that left Ali wary of her friend? Maybe something happened and Ali knows it was a Liar, but isn't sure which Liar...
She's trying to break the Liars apart. Of course, as Spencer pointed out, Ali hasn't always been the most honest with the Liars. We're not ruling out the concept that Ali really does want to sow discord amongst the girls. Showing Emily special favor and claiming the other Liars aren't trustworthy is a good way to do that.
Why do you think Ali said that? Let us know in the comments below!