As long as you're on antibiotics, it shouldn't be contageous. Give them a day or so to kick in & start swapping body fluids. She's already been exposed because of the incubation period of the bacteria. You have to have the combination of your resistance being down & being exposed to the infectious agent @ the same time to develop an infection. Her resistance is probably not diminished, or she'd have it too.
What kind of antibiotics did your Dr. prescribe?