So among all of the name-calling and general awfulness towards Alana, there is actually something which caught my interest. And that is the idea that Alana has somehow left her rationality behind the moment she became involved with Hannibal. Which, quite frankly, is ludicrous.
She has always stood with Hannibal - there was never a doubt in her mind in series 1 and even as she wanted to believe the best of Will in series 2, she still denied the possibility that Hannibal could have had anything to do with what happened to him. She didn’t just sleep with Hannibal and promptly ended up deluded by the power of sex; she has been absolutely consistent in her opinions on him.
What changed wasn’t Alana. What changed wasn’t the relationship between her and Hannibal. What changed was Will. She is certain (and correct in the assumption) that he attempted to have Hannibal killed. That he asked another person to murder Hannibal. This is the only definite thing which Alana knows in this situation, the only new fact she has to go on. Everything else is suspicion and accusations, nothing more. So her decision to turn away from Will and take a definite step towards Hannibal is in fact based on reason.
The person who was accusing Hannibal tried to have him killed, proving to be not who she thought he was. Jack’s growing distrust of Hannibal has led him nowhere. She was even at Hannibal’s house the night the Chesapeake Ripper committed a murder. Miriam Lass exonerated Hannibal when he was under suspicion again. She has known Hannibal for much, much longer than anybody else - they have a long-standing mutual admiration which precedes all of this mess.
These are her facts
It is absolutely reasonable for her to assume that Hannibal is innocent.