I (in general- much less here than IRL) often find myself holding back from even disclosing my atheism, let alone discussing it, largely because I don't see it as productive. I'm not going to talk any religious people out of being religious, and I don't want to anyway. And, unfortunately, experience had taught me that religious people do often try to convert you if they know you aren't "a believer" or however they identify. Especially with certain brands of protestantism (ex. "born again," evangelical, etc) a very strong culture of, essentially, pushiness.
For me, it's annoying and unwanted when someone pushes religion on me, even to tell me god loves me or I am in their prayers or whatever, but I know it is usually well-meant, so I try to take it as that: a (religiously) spazzy well-wish. That's how I've been perceiving Hannah. Some of her persona is probably a front, a fair bit of it is her own version of spazziness, but I do think she's primarily trying to be nice and trying to be liked, and religion is her thing. Not my cup of tea but if it makes her happy, that's great, and as far as I can see she's not hurting anyone.