I had it constantly from about 18 weeks BLEH so I know what you mean. My midwife never seemed overly concerned, so I wouldn't worry too much. In-Liven is a good idea. Someone told me to limit bread and vegemite and some other things (yeasty foods I think) but vegemite was a craving, and you can't have it without bread, so I never tried it...
Something that worked for me was to give that area some air time, I would go no-nickers after a shower and to bed. I always thought it would be better to wear a liner to try and 'dry' the area, but having absolutely nothing there worked much better. Also, try the liners that are breathable, that was another thing that helped.

Hope you get it sorted, thrush sucks!