I'm curious why you specifically don't eat citrus fruits? I have the same thing but the milder version which only hurts during intercorse. I've been told by many that problems might be caused by my body ph being too acidic. Citrus fruits is the most powerful thing to make your body more alkaline, believe it or not. They taste acid but turn alkaline in your body.
This might be worth a try to read up on, the forum Ask MH knows a lot about this issue. I've just started eating lots more citrus to see if it helps. I also tried Coconut oil and it did some good. It kills bacteria/fungus/ parasites and is good for this area they say.