had a rash of red spots under both breasts now that have come and go since last August, they are red, itchy and sore, could this be a fungal rash?

Yes. The skin under your breasts are often (since its warm and often moist) where fungal infections "set uphouse' Over the counter LOTRIMIN (clotrimazole) cream may help and if not your GYN can treat with Prescription anti-fungal preparations. Hope this helps! Dr Z.