Three years ago, I got a painful rash on my right ribs that lasted 1 month. I still have that severe pain today that causes difficultly breathing.?

Not 100% clear. It would help to see a photo of the rash, but consider whether this is post herpetic neuralgia. This condition causes a rash that affects strips of skin called dermatomes that can cover the ribs. The rash can be very painful, and the pain can last after the rash is gone. Sometimes a medicine like gabapentin helps. Was the rash caused by zoster?