I agree with another answer in that you are welcome to work with the buyer and their agent directly. You should have their contact info on the offer you received. It sounds like there is something we are not being told such as why your agent felt so strongly that they decided to walk away from you. The managing broker of the firm you hired to represent you should already know what the story is, so you could talk to them as well.
When you say she is not getting her way, we tend to think "what a knucklehead?", but the reality is that she would have to feel pretty strongly to do this, so I am certain you are not disclosing enough data for us agents/brokers to be helpful.
You ask about recourse, and this is hard to answer without knowing the circumstances. Ultimately the Washington State Department of Licensing oversees our licenses, but your recourse starts with the managing broker, the firm, the Multiple Listing Service, Association of Realtors (if your agent is a Realtor), and of course, Dept of Licensing. Attorneys can cost you additional fees which you may or may not recover, but many will do an initial consult free of charge.
I would really be curious to know why she walked away though. A lot of sellers do not "get" the market, and have very unrealistic expectations. Ethical issues are very common, and our job is to represent the buyers and sellers, not to BE the buyers and sellers. The clients make the decisions often based on our guidance and knowledge. Many of us face chalenges daily but to walk away would have to mean there is something serious at question.
Good luck and I hope it all works out ok.