The course of the disease is usually 2 to 3 weeks, and then the blisters dry and the scars are left with temporary reddish erythema or pigmentation. Normally , shingles won't last for 8 months. People with low immune function, like tuberculosis，HIV ,and patient who take mmunosuppressive drugs , have long course. I never see a patient have shingles lasting for 8 months. what is it like? always blister and never get dry? have you see a dermatologist? was she clearly diagnosed with shingles? you should see the dermatologist again.