what should i do with my rabbit?

  the vet told me that my rabbit has a neck problem (not really sure what it was called) and cause of that she kept drooling which irritated her skin and didn't allow her to eat. he gave me an injection to give her and i followed his instructions. he also told me to feed her fiber like lettuce and apples. i did at first but then i started forgetting later. well a couple of weeks passed by and now she's gettting it again. should i try going to the vet again (which is kinda bad since it's expensive) or should i try feeding her more fiber and see what happens?
It's life is in your hands. Take care of it the way it should be taken care of. I would go the fiber route and see how that goes for a week or so. If worsens then take it back to the vet. Don't just give up on it. NO animal deserves that. I hope it works out.
Do as the vet says to do they know best because that is there specialty (animal care). Just like you would do as your doctor says do as the vet says.
Feed her unlimited grass hay along with veggies and she will get enough fiber. You need to start taking care of her or she will suffer.
Start feeding her more fiber like the vet said, and from now on remember to do it continuously.
Rabbit stew is an excellent source of daily meats and fiber. just saying.
sorry about this but ....... put the poor animal out of its misery