Hi Dillinger
I'm not Brains of Britain with all this but rather than use Metformin why don't you have a go with Apidra to see how that affects yr bg levels?
You're probably facing some resistance with insulin due to the amount of protein and fat you are eating. But just to compare, before I started PP (pump) my insulin to carb ratios were similar to others using Levemir and Novorapid. Mine being - 1:4cho at Br, 1:8cho at lunch and 1:4cho eve meal. What are your ratios?