Uh-oh, you seem to have a storygamer on your hands. Some newer systems such as PBTA and Forged in Darkness have a “pass the GM stick around” mechanism, and borders between players and GM are slightly more fluid. I presume this is her first time playing a traditional RPG, so I would recommend taking her aside and telling her that in D&D (which I assume you’re playing) players play only their characters, while the DM plays the rest of the world.