HELP! Baby stopped taking bottle!

HELP! My baby (11 weeks) used to love feeding from a bottle (breast milk). But a week or two ago, she suddenly stopped taking the bottle. Whenever she sees it or we place it in her mouth, she's starts crying and fussing immediately. The only thing that she craves now is mommy's breast!

I don't know why she's had a sudden inexplicable change of heart. We've been bottle feeding almost exclusively from the beginning and there were never any problems until now. With the nearing return-to-work date, I'm terrified that the baby won't come around to the bottle in time. We've tried faster flow nipples, different bottles/nipples, different breast milk temperatures, different positions and environments... no luck. She simply won't accept anything in her mouth (other than mommy's breast) without instantly crying!

Has anyone experienced having a baby who suddenly stops taking the bottle after successfully doing so almost exclusively for months?? Please help!