bottles and breastfeeding

help!! My almost 3 month old is refusing to take a bottle! we first introduced it when she was about 4 weeks old with no issues. from then she would take then occasionally if I wasn't home or wanted dad to feed her. Then one day ( unfortunately 2 days before I was supposed to go back to work) she decided she didn't want to take a bottle anymore.. she takes a pacifier just fine but when you give her the bottle she either just chews on it or screams like she's being tortured.. it's frustrating for dad when he is alone with her because he can't do anything to help her.. any advice??