What Causes Recurrent Vaginal Infection During Menopause?

i have been menopausal for 1 year and am taking bio-identicals of progesterone/estrogen and testosterone. the hormones are doing great for keeping my energy up, libido active, and hot flashes to 1 - 2 a night. My issue is, I frequently experience yeast and vaginitis infections. I feel like if it s not one it s the other. I do take diflucan for the yeast infection which it does take care of the problem, but within a few weeks or months I get another yeast infection or worse vaginitis and have to go on metronidazole and then flucanozole. I am a cyclist and use a small amount or Monastat cream while riding. I get out of my sweaty bike shorts as soon as i can. Any suggestions of prevention would be extremely helpful