Are you taking ANY probiotics? If you are not, start taking them. Get a really good one with lots of different strains. Primal defense is good so is Udo's. Take them at least 3 times a day. Stay on them until the thrush clears up. Get some betadine and make up a douche with a couple of capfuls of betadine to water and spray up in your vagina and hold the water and then forcefully expel to get the candida threads. Do this in the evening before you insert any monistat. If you are too sore to do this, wait until it's less sore. The betadine is antifungal.
Eat fermented, (unpasturized saurkraut for instance) foods and plenty of yogurt if you're not lactose intolerant.
Following the anti-candida diet would be good too.
It sounds like you were on some really strong Antibiotics .