how to stop getting UTI’s


ever since i’ve had my boyfriend (1 year) every 5 months or so I get a UTI or a yeast infection .. I don’t understand HOW .. I shower & pee after sex always , I have very good hygiene in general and I only drink water , I don’t drink juice or pop .. any thing else I can do!? this is driving me insane!!!! (currently having my second UTI , last one was in february)