Hi Jon. I am sorry your fiance' has been sick for so long.
Has she been tested for the co-infections ticks can transmit--Babesiosis, both types of Ehrlichiosis (HME & HGE), Bartonella, and Mycoplasma? This is very important. Many people who have Lyme are co-infected, and it may affect treatment choice and progress. Many Lyme doctors believe co-infections need to be treated first.
I am not familiar with hydrogen peroxide treatment. Why is it supposed to be effective? Have you spoken to other people who have Lyme who have done it? I higly recommend researching this thoroughly before starting it.
Acidophilus is very important, and it should be taken in proper doses on a daily basis. What strength is the one she whats Sarah to take? I do not think taking it three times a week is enough.
I do not believe that 500 mg of Cefuroxime daily is in the treatment range for Lyme. I believe the typical dose is 2000 mg daily. If you have not done so, I recommend reading Dr. Joseph Burrascano's 2005 Diagnostic Hints and Treatment Guidelines For Lyme and Other Tick Borne Illnesses at http://www.ilads.org/burrascano_0905.html He is one of the top Lyme doctors in the country, and many Lyme doctors follow his protocols. He discusses meds and dosages starting on page 17.
You may want to consider getting another opinion. Have you been in contact with any support groups? I found the following Lyme support groups listed for OR:
Oregon Lyme Disease Network
Oregon Lyme Network
These may be good sources for information and doctor referrals. It is very important to learn as much as possible. I also recommend the books "Everything You Need To Know about Lyme Disease Second Edition" by Karen Vanderhoof-Forschner and "The Lyme Disease Solution" by Kenneth B. Singleton MD.