Hey surprised, just wondering - have your nipples been swabbed for infection at all? ABA counsellor said thath infection is a very commonly misdiagnosed (as thrush or mastitis) problem causing nipple pain and it's a good idea to get it checked out if you have recurring problems. If they swab they can give you the specific antibiotic for the infection. just a thought.
Anyway, I hope this is the end of your troubles