I believe that they can heal on their own, but you have to be willing to be very patient. I had one bugger on and off almost all race season. It would go down, then get irritated again. Fortunately it was not affected at all by saddle pressure so riding was not a painful, but yeah some pairs of undies were not good... (I really like boy shorts since they don't have any elastic in the sensitive area)
Now that race season is over and I had a couple of rest weeks its finally almost gone. I just hope it stays gone.