Was the daughter on the spectrum? [Spoilers]

It certainly felt that way for me. I think we as an audience would've been a little more sympathetic towards her actions at the end if they gave us a little more insight on her background. It's just hard to imagine a child being that bold and heartless enough to abandon their family in the middle of a crisis for their own personal gain. The signs point to her having some unexplained issues or she's just that much of a dick...