Just as an addition to P-tree's great post - I would get Kidney bladder tea and tincture from Doctor Schulze (or you can make your own). I would do the 5 day K/B cleanse (click on Schulze up top and it will have the link there). I also would rev my immune system up once per month with 2 oz of echinacea.
Another way to keep them at bay is with pure, no Sugar added, cranberry juice. It also helps to stop bacteria from sticking. My fiancee has bladder infections 2x per year until we met 8 years ago. She did a course of acidophilus right after she finished up a course of anti-biotics (before we met....). Following that I ordered CranMax for her from www.lef.org
She takes one at night. She also switched from soda to a dedicated distilled water drinker.
The results? NO infections in the past 8 years. NONE.