She's a walking contradiction and a bit of a hypocrite.
Hannah is an insomnia and, thus generally usually found to be on the brink of exhaustion. She also has OCD where she must repeat certain tasks, she finds comfort in even numbers. Additionally she's a germophobe and is obsessively washing her hands. Overall, Hannah is a nice person, just a little spastic.
Hannah was kicked out of her house as soon as she was finished with high school because her parents could no longer deal with her OCD.