AJ - you've done so well in your weight loss so far, and I'm sure you'll continue to. The dietitian I saw last weekend explained it to me that when you're overweight, your adipose tissue (fat) surrounds the cells, which stops insulin working, thus 'insulin resistance'.
Fingers crossed it all works out for you. I have to go and have a fasting BSL test, so I might be jumping on the bandwagon with you.