glad you're feeling better, Sally... and hope it clears up totally... like, really swiftly!
I had a running battle with coldsores (Herpes Simplex I) for many years...
my doctor prescribed Acyclovir, that cleared the sores up, and then, they stopped coming (for some odd reason) after a couple of years on a daily dose.
I also had a few bouts with oral thrush, and sometimes, BOTH thrush and coldsores at once.
as to "why at the holidays" well, that's when I *always* got mouth and face sores, my doc said it's the stress, lowers your immune system, and your ability to fight off yeasts and viruses...
since I had little kids at the time, I used Baby Orajel, and that helped.