Hi C.,
Congratulations on your baby girl! It sounds like you are a good mom; concerned about doing what is the best for your baby.
You have already gotten some good advice, but I'll just throw in my 2 cents worth. My daughter also went through a nursing "strike" at around 8 months. I was already pumping while at work, so I just pumped again after she finished nursing and gave her my breast milk in a bottle later. She never really went back to nursing as strongly as before, but we kept it up and she got some from me and the rest that she needed in a bottle. The nursing time was so special for both of us, and I wasn't ready to give it up at 8 months.
I definitely think that she should still be getting most, if not all, of her fluid from milk. I'd give her any breast milk you have pumped instead of water. Pumps are pretty easy to use these days. I don't have a recommendation for one (it's been 10 yrs since I used one ;-), but I'm sure some of the moms here can give you one.
Also remember that while doctors have special training, and you should listen to their advice, not all doctors are sold on nursing. Women have breast milk for a reason. That is the best food for your special little girl! As long as she is healthy and gaining weight, she should be fine.
Enjoy your family, especially this precious time when your daughter is small.
Regards,
L.