I recommend starting a leadership program like NILIF. Also, work on solid obedience. If the dog is hungry it will have motivation for the food. Withhold a meal and then try training. If that isn't enough, withhold 2. This will work. Make sure the dog is getting lots of exercise.
You may have to manage things for while until you get things calmed down. It's important that you don't allow these behaviors to continue. I would put a drag line on the dog so you can control her better in the house. Keep her with you and monitor her interactions with the other dog.
Females sometimes just don't get along. I hope this isn't the case.
When a dog saves the life of a man, it becomes clear that partnership knows no bounds.
Fama - T.E.D.D. OEF XI-XII (GSD)
Marshall - T.E.D.D. OEF XII-XIII (Lab)
Lucian - Med Alert (Cane Corso)
Pud - the old man (Pit x Lab)