Oh do I feel for you! This site has such a great article on this:
http://www.drmomma.org/2010/05/treating-and-preventing-th...
I hope you find something that works for you. For me, I finally had to cut out sugar, milk, and soy products. And I took a probiotic. This was the only thing that worked. I reintroduced sugar and milk and soy after there were no signs of yeast for a while. My doc had given up on me--she just said she was so sorry, and didn't know what else to do. I finally found my own solution. I kept breastfeeding (made it another year and a half!) but it was tough until the yeast went away. I had to forego the whole doctor thing and pills and creams and starve the yeast, and feed the good bacteria.
A good probiotic is a yogurt called Bio-K (in the fridge section of the health food store) which is very expensive but super-high quality. A good pill is Lactobacillus (or something like that). You can paint your boob with it too, and give some to your baby. He certainly has a yeast overgrowth, and you certainly have one too. It's systemic, and you have to treat yourself and then take away the yeast's food. Have you been craving sugar? The yeast eats it all up and makes you want more, so you feed it more and it just gets worse. Nasty stuff.
Best of luck to you. You can take care of it pretty quickly with natural stuff. I bet you'll be feeling better soon!