Hi, I Am A 54 Year Old Female, Just Had

Hi, I am a 54 year old female, just had a check up/follow up after having a case of shingles. Janurary of this year. My doctor prescribed Valacyclovir 1mg tablet 3 times daily for 7 days. Had follow up 3 wks after treatment completion. (I also have lupus - since 1993) Now I find myself with the shingles once again. Doctor called in prescription, prescribed Valacylovir as before with Zovirax 5% cream this time. This is my 4th time with shingles in a year. I also had HIV testing February 2015 during my yearly exam, tested negative. Recent blood work doctor stated all came back clear, blood ans well as urine testing. Why do I keep getting the shingles. I'm told because I'm under 60 years old I can not get the vaccine. Please advise.