Help Much Needed for Horse

I don't know if animals are also covered on this forum, but I'm hoping someone could offer some help for my horse, Pride.
Back in March, I noticed the first hard lump about the size of a nickel on his face. I had the vet check it out and she said it was a fracture. I didn't think it was because there was never any heat or swelling, and he was letting me rub his face without a problem, didn't seem to be in pain. About 6 weeks later, another hard lump appeared, and the first one seemed to have grown slightly. My trainer said it was bee stings, so I gave him Apis 30c, but there was never any change.
In another 3 weeks, a few more lumps were noticed (the changes pretty much happened overnight.) I was starting to suspect bone cancer, and I called the vet out again to take x-rays. I was hoping they would provide some definitive answers, but they did not. The vet said the most likely diagnosis was Equine Suture Line Periostitis. I asked her if there was anything that could be done, her answer was no and that more lumps would just keep appearing. I looked up periostitis and saw that one of the symptoms is pain. I'm concerned that if the diagnosis is correct, my horse will be in pain for the rest of his life. The vet was very nonchalant about it, which frustrates me a little. I gave Pride Symphytum 30c, just incase there was a tiny fracture, but again, there was no change. I tried Ruta 30c as well, but have not noticed a difference.
As far as his medical history, he had a moderate case of Lyme 2 years ago, was put on the Doxy, but I pulled him off it after a week, and gave him Ledum 1M which seemed to have done the trick and cleared up the symptoms. I did not have the Lyme titer redone. Do you think I should? Other than the Lyme, he has been pretty healthy. The lumps seem to only be on his face, his legs and back are clear.
I do have pictures, if they would be of any help.
Any information or suggestions would be greatly appreciated.
Thank you so very much.
~Robin