My thrush won’t go away!

For the last 6 months I have had thrush every month, I’ve tried OTC medication which will work for a couple of weeks and then the thrush returns 😩 I have been tested for STI’s, tests have come back negative. What can I do to stop it?! It’s driving me insane and is seriously affecting my sex life with my partner because I’m uncomfortable with it! Please help.

The picture is the start of yet another infection and it gets a lot thicker and chunkier 😳