I had unprotected sex with a woman over two months ago.  She said she was clean and on the ring.  About three days later my scrotum was on fire and blood red.  It continued that way for a good two weeks.  Now still two months later, redness is still there on my scrotum.  Burning comes and goes.  Sometimes a little itchy but whole region is generally tender.  The redness has been very localized, not moving or shrinking or growing.  It starts right at the base of my penis and is on the front of my scrotum.  Redness stops on the sides and underneath.  Penis is unaffected.  Sometimes I can feel tingling on my scrotum.   

Doctors first diagnosed yeast.  Tried Diflucan and Nystatin to no effect.  Doctors then thought bacterial so put me on Cipro for a week, no effect.

Had some Triamcinolone left over from a rash and tried that - no effect

Had an STD test.  All negative except for HSV1 which I am pretty sure I have had for years just never tested for before. Doctors put me on Valaciclovir for a week.  No effect.   

I have been taking L-Lysine, as I know it helps with HSV1, but no effect.

Tired different body soap, no effect. 

Dermoplast give some temp relief but burns when it goes on probably from the menthol. 

Changed underwear.  Cant wear cotton as it chafes and makes it worse.  Boxer and briefs are out. Compression underwear with nylon/spandex works best as it keeps my scrotum locked up tight so it does not move. 

I have found a lot of posts on health forums from years ago with many men suffering from the same problems, no one ever posts a diagnosis or cure. 

Anyone have this before?  This is ridiculous that no one can figure out what it is.