I like LillianGish's summation of what was going on.
I do think Juliet did it. No way round that, and she hasn't denied it. I think there will be surprises though, but they won't be about who did it, just why or about the family's backstory.
The doctor friend has a lot more to say IMO. I expect a big speech from him. And a surprise new character in the form of the actor friend of a friend of someone on this thread.