Kill 'em with kindness?? It cannot hurt to try. I don't know if this is feasable or not, but could you approach the nurses privately and say something like, "Have I done anything to offend you? I'd really like to keep working with you and I think you are a really competent/knowlegable nurse. I hope I haven't done something to upset you. Is there something I can do better?" and so on. Most people avoid confrontation and if you were to compliment her it might open some doors or start a dialogue for you to work things out without having an all out war. If this isn't a reasonable idea or doesn't work out, I would think filing a formal complaint using the chain of command like the others mentioned would be your only recourse. Please let us know how things work out!
I wanted to add that I have had to swallow my pride and be humble in the past to keep things pleasant. Although I hated it, I sucked it up. Even if you are in the right, it is hard for others not to accept an apology or compliment! Most people find it hard to be nasty when you ask for their help and show them kindness even if you are seething below the surface. It is not an easy thing to do but it may help. Good luck!