Ooh, fab - thanks very much for this
With regards to the spoilers, I'm not sure when the 'betrayal' is supposed to happen either. I think everyone is probably right in that it'll be Rob going against Aaron's wishes and alerting someone to his suffering. The 'struggling without Aaron', I suspect might be to do with Liv - maybe he struggles to know how to handle the drinking situation.
I feel like we don't know enough but I guess that's all part of the plan...frustrating for a spoiler junkie like me though!