Oh dear. So how do you treat? As you have been? I know that lots of things that are normally contagious in a flock can many times affect only one bird, who for whatever reason has lowered resistance compared to everyone else. It seems to work that way in our flock.
Thought I'd pop in and see if I can offer some advice.
It does look a bit like Fowl Pox, though I have no experience with it. :/ I did look through the whole thread though and I found it amazing how much her face swelled! I've never seen anything like it!