Another thing I remembered. Lichen Planus is supposed to be stress-related. As are cold sores. When I had that sore I mentioned before, one web site said to dissolve a sedative pill in water and swish it in the mouth to get relief.
Now, I don't know if you took some Valium or whatever and swished it in your mouth if it would cure the LP. But maybe it would soothe the affected area, and you sure would not be worrying as much.
In retrospect I am sorry I did not have my doc call this in when I was in so much misery. That was the worst unhappiness I have experienced in a bodily way in the longest time. It was maddening, and I hope you feel better soon.