I don't think she wants to BE Janelle at all. They are stuck in a house, whats better to do. My friends wear my stuff and they don't want to be me, and im the same way with them. Janelle let her borrow those things, its not like she was just taking them from her. The crown was out and Erika put it on, not a big deal.
I think the whispering is a joke since they can't hear what Janelle and Will are saying they do it.