It could very well be that it is winter time. Rabbits do require a certain amount of light per day to be receptive to breeding (at least that is what I have gleaned from reading responses from breeders). In some larger scale productions, they have timed lights so that the rabbits will be more receptive year round.
I know that quite a few other breeders have issues getting does bred in the winter as well. If temperatures are low enough to still be freezing water, then you could try waiting a month until it warms up some to try again.
You can try having a look at her genitals and seeing what colour they are. If they are pale, then my best guess would be wait until it warms up a bit. If they are nice and dark red, then give it another try.
-Dawn