You might want to see a doc. I've had some topical infections (don't know if they were fungal or bacterial), and they didn't clear until I got the appropriate cream (steriod/something?). One summer, I had one that just wouldn't go away. I would also try to keep it as open and breathable as possible (as you would with saddle issues) - i.e., sleep in a nightshirt and pass on undergarments.
Otherwise - no idea.That sounds miserable.