Having been through a flood and losing a lot I surely can sympathize with you!!! I would think that because it was not a burst pipe, but her negligance, her home owner's policy should pay for all the damage and your losses....
(((HUGS))) I know that you are probably still in shock and in the process of hauling out the damaged items.... Take pics of everything single thing that was damaged if you can...it will help in getting them replaced.