I had a similar experience in the hospital with my 19mo. He didn't strike, but the only thing he was eating/drinking was breastmilk - and ALL the doctors/nurses were SO glad he was still nursing!! I got so many, "WOW! Thats great that you're still nursing! What a lucky little guy!" It was also great b/c he wasn't vomiting at all, he was just really sick, so everyone was relieved that he was taking milk orally and not vomiting and had no diarrhea.
I'm glad that you're hospital was supportive as well! And, I really hope your dd gets better soon - its so hard when they are really sick.