Hi Midnight Shadow and sorry to hear about your issues with thrush - as a fellow sufferer of persistent thrush (not glabrata for me, but parapsilosis) I feel for you.
You can buy pessaries containing boric acid in the UK in the form of 'Boots Dual Action Thrush and BV pessaries'. They were suggested to me by a consultant dermatologist and (crossing fingers frantically here!) really seem to have helped me.
I had no idea you could get boric acid pessaries from Boots and was amazed when the dermatologist mentioned them! You can buy them over the counter and (unlike the azole medications) there is no upper age limit. They come as a seven-day course and the instructions say to use them for a second week if needed. I used them for two weeks and then, after a gap of a few days, used for another week because things still didn't feel quite right.
I have a couple of packs put by, as I'm sure the thrush will recur (I'm being treated for Lichen Sclerosus - hence the dermatologist - and using steroid ointment for the LS apparently really increases the chance of thrush. I was prone to chronic thrush anyway, so the steroid was a double whammy for me). For now though, I've been pleasantly surprised by how well the Boots pessaries have worked.
Just wanted to let people know about them in the hope that someone else might find them useful.