Cauterizing is wonderful, mom. Don't be afraid! I promise you that you will be so happy to not have these massive nosebleeds anymore. My son would soak towels. I would take him to the doctor everytime so that he had a medical record of them. He needed help!
Then they sent me to a ped ENT and she put an anesthetic gauze up his nose and sent him into the waiting room to play. 20 minutes or so later, she used a "stick thing" to do it. He didn't feel a thing! The uncomfortable thing was laying there with her doing work in his nose.
It was a godsend.
Fast forward to the resuming of bloody noses several times a day, but not towel-soaking ones. My son was 16 years old by then. I took him to another ped ENT and he told me that several blood vessels were very close to the surface. He cauterized right there on the table. My son was very happy.
He still gets nosebleeds because he is prone to them, but they aren't terrible. I highly recommend talking to the ENT about it - NOT the ped.