Ok, so it does look like fur mites, and you said you can't get to the vet. Fur mites aren't fatal unless left untreated for a long time. If you had the option to go to the vet, I would do so, because they would be able to give you medicine to cure the fur mites. However, tea tree oil could work. I researched it for a while, and tea tree oil is common for getting rid of mites, ticks, and other small insects. Most bunny owners claim that it works on rabbits.
Link to the website, scroll down to skin mites -
http://florida4h.org/projects/rabbits/MarketRabbits/Files/NaturalRemedies.pdf
Basically, get some tea tree oil and dilute it with water, then gently spread it on your rabbit's neck.
I've always heard that Listerine works, but I'm not sure if you should try that.
However, this is just a suggestion. Just like any other essential oil, I'm not sure that tea tree oil is safe, even if many use it to treat rabbits. I would wait for the input of others.
I'm sorry your bunny is going through all this, but hang in there. She will get better! Update us everyday!
Best wishes~
Remy