Diflucan and Candidiasis under my arm

Hi all -- I am a reasonably healthy 38 year old man. I find myself with a yeast infection running aggressively under my right arm pit and to a lesser extent around my mouth and infrequently around my groin. The background is this: In May, 2001, I sought treatment for a prostate infection -- turns out I had had this infection for a decade and never knew what it was. I was put on Cipro for 5 months. Prior to this, I never used to get sick. After this treatment was complete, I noticed that I was getting infections every 3-6 months. One thing or another, sinus, throat, chest. Each time, my physician would give me an anti-biotic which I took without much question. Augmentin, Bactrin, Zithro, and the like. The last time I was on an anti-biotic was last September (2002) for a strep throat. Early last January, I noticed a rash developing under my right armpit. I went to the dermatologist and he told me it was a yeast infection. He also was greatly concerned that it was under my arm. When he used terms like HIV and diabetes, I went immediately in for a full physical with blood work. I am NOT a likely candidate for either. My diet is reasonbly good, I exercise a lot, I do not engage in unsafe sex, and I consider myself above-average in health. The tests from my physical showed exactly that. Everything came back perfect -- no worries of serious illness. But this damn thing under my arm was a problem, and my dermatologist treated me 5 weeks ago with Nizoral and Nystatin. I cut way back on my already-low Sugar intake (I live on a healthy Diet normally) and have cut out bread, fruit, sugars, and anything that could contribute to the yeast growth. Basically a do-it-yourself Atkins approach. I do not smoke and rarely drink alcohol. I added large quantities of pro-biotic supplements, including of course acidophilus, after doing a lot of research on candida. OK, so everything was going fine until late last week when this thing started to explode again, this time irritatingly, under my right armpit and to a much lesser extent around my mouth. HELP! I have not found any instances of others with my specific symptoms and now I find myself taking Diflucan (fluconazole, 150 mg for 3 days, followed by once a week for 4 weeks to come)) at $25 per pill...which is working just like the Nizoral did. I'm praying this is the solution and not just a suppression, and I hope I'm not causing more trouble to my system.

Anyone's relevant thoughts would be hugely appreciated.