They have fake blogs for the characters after an episode airs. Aiden's blog mentions that he only remembers blacking out after drinking tons of blood, but he has only been drinking the blood bags. This implies that whatever is causing this isn't Aiden.
Hypothesis: Aiden is bring possessed by something, it is a side effect of the werewolf blood, or being in the coffin for a year messed him up badly and he has some type of split personality. Maybe Sally's backed up theory has some weight, but not in the way she is thinking. Kinda like vampire "blue balls"...sex/intimate situation with no feeding makes him really want to feed.