I have celiac disease and can attest to the fact that it can aggravate inflammation in other areas of the body. Be sure you're not consuming glutens in less obvious sources. Use gluten free salad dressing, for example, since most others have hidden glutens. It is hard to go gluten free but it is worth it for the improved health.
I would also use a good probiotic like Natren Healthy Trinity for your gut health and to help eliminate yeast overgrowth there (yes, it can affect other areas). This probiotic is not cheap and must be kept refrigerated but it is worth the cost. Reducing Sugar intake can be very helpful (esp. high fructose corn syrup - become a label reader). Some people chew and swallow cloves of garlic from time to time, and claim it helps.
The above things will be helpful for your health.
This article has some good information, esp. the tea tree oil idea:
The tea tree oil can be applied externally (and as a vaginal suppository) and helps with inflammation as well as itching. Be sure to get a genuinely high quality tea tree oil (it is definitely more expensive than the 'diluted' brands). Ask at your local health food store. You may have to use it several times a week for a while. Tea tree oil is very effective for treating inflammation and many kinds of infections.
I would also ask your doc to test your vitamin D3 level. You will likely need to supplement to get it up above 50. A deficiency can complicate things for you.
Besides keeping very clean and dry, a good multivitamin to be sure you cover your bases is a good idea.
You may have some undiagnosed chronic infection(s) which need treatment, also (such as Epstein Barr, HSV1/2, etc).
Try to find a good doc who will look at this possibility and order the appropriate blood tests. What is appropriate will depend on your history and symptoms.