Can you help with a diet sheet for type 2 diabetes?

I am not diabetic, but my chemotherapy & steroids have upset my sugar levels – high sometimes 29.5 low 3.1! I've been put on slow release Metformin to try and control it. I keep asking what I should and should not eat, but I keep being told – just eat a healthy diet! I already do and obviously there's more I need to know. I knew someone once with Type 2 and he used to have to eat a sandwich at a certain time of day and avoid certain foods. Please help – it's bad enough trying to survive Stage 4 bowel cancer which has now spread to both my lungs and my liver, and the Deep Vein Thrombosis I get as a side effect of the chemo, so I should be pig sick to die of Type 2 Diabetes and the side effects!!

Help! and Thanks.
JUDY A – yes it's true, I do have all those problems! but I made 67 in November so that's good. Diagnosed with Bowel Cancer Stage 3 in June 2002, had chemo and it went away until some time in the summer of 2005. Scan in September discovered at least 5 tumours across both lungs and one in my liver – had chemo from November 2005 to June 2006, then time off, but a few more arrived in my lungs during the time off, so started another course of chemo in October [another 6 months] I feel fine, just needed help to do the right thing with the sugar problem. Thanks for your info – sounds just like the man I knew years ago – who always had a sandwich in his bag incase he reached a certain time! Hope you read this!