Deanna Leigh has a great attitude about this and ideas.
The thing is, this is called 'post traumatic stress.' You CANNOT "rush" her to get over it.
AND, per her age.... having night-time fears are just a NORMAL part of development and their growing cognitive development. ALL kids this age and older, have night-time fears. Even my 6 yr. old daughter does AND her friends the same age.
Sure, maybe it is inconvenient or irritating for the adults... but, this won't last forever. You need to comfort her now... my kids, when needed, sleep on the floor futon in our bedroom too. We don't mind. They are just little kids and one day they will not need us. My kids, despite our "co-sleeping' on the floor of our room, are very independent and confident kids.... and very well self-directed and secure in themselves. The bonding is good for any kid.
Your girl is obviously not over the trauma of the earthquake... for a child, they don't grasp that it happened "3 weeks ago"...they don't know what 3 weeks are...all they know is that it feels like it happened just yesterday. So for you and your husband, well that may seem like a long time ago... but for a young child, it is NOT.
She is showing that she STILL needs help with this, she is scared witless. She gets up in the middle of the night and PANICS and screams... this shows "fear." Basic fear, which for her is REAL and actually happened to her, not in her imagination.
I would try and be more patience and compassionate. These stages are phases and for her it is post traumatic stress.
Ask your Pediatrician also, how you can help her.
All the best,
Susan