LOL, I've written characters like that too. Maybe you could use the Christian idea of a glorified body (which can pass through physical objects, but can also make contact with physical objects, and exists in both a physical and spiritual plane). Perhaps she's already died and rather than becoming a Force ghost, strictly speaking, she's adopted a new form of body (perhaps Force ghosts are able to form bodies if they wish). Or maybe she is a Force ghost, and Force ghosts can interact with their surroundings, like how we saw Obi-Wan sit on a log in ROTJ. That could explain a lot about her, as well as providing an explanation for Obi-Wan's "more powerful than you can possibly imagine" and his sitting on a log.