I've never had your experience... however, other people I know who get frequent bladder infections swear by drinking cranberry juice. Something about the citric acid making the bladder environment inhospitable for the infection.
Been there, MOSTLY annoying, until my previous doctor back in Belgium told my mum that I had to get my current doc to prescribe me Furadantin (nitrofurantoin).
Within 3 days it was all cleared up, but you need to do a 10 day course. Thereafter if you are very prone, you continue with one a day as a preventative for x months, then go off it and hopefully be fine.
You make sure you always have it at hand and as soon as you feel an upflare you do the above again.
My doc said she's happy to prescribe it for me so I have it around all the time and to take it when needed. It's specifically for UTI's.