You can of course get angry (sounds like you have every right to), and get so down that you just abandon any attempt to get things under more control (ie. feel better) but neither will help you in the slightest, yeah? What you need to do, whether your nurse, doctor or anyone else is a pain in the backside, is to get as informed as you can be and put yourself in control of your health wherever you can. A low carb diet will reduce blood sugar levels and help with weight loss.
As for the rubbish or lies you have been told regarding this steroid as a cause of your diabetes, it may be worth noting the following :
I was diagnosed with Type 2 after two months on Prednisolone following a kidney transplant. I was warned in advance by all the renal doctors, two pharmacists and one nurse on the ward that this drug could increase my blood sugar levels and lead to Type 2 diabetes (particularly because I would be on the drug for a long time). over a year on and the kidney is good and my blood sugar is managed well with diet alone (I was originally on Gliclazide). I have had several doctors since (at regular clinics) confirm that Prednisolone caused my diabetes. I'm fine about this as I'd rather have diabetes than have to face dialysis for the rest of my days (and I was well aware of the risk in advance..and I'd make the same decision again). Some doctors like to say that so called Steroid Induced Diabetes (yes that's what it is called) only triggers a predisposition to diabetes due to lifestyle or family history. I have never been overweight and no-one in my family ever had diabetes (except my brother..who recently had a similar transplant and got diabetes..from the same steroid!). My renal doctors agree that the steroid was directly responsible, and having greatly reduced the dosage, my spikes have dramatically lowered. The advice is that if someone takes certain steroids (particularly Prednisolone) for a short period, increased blood sugar may well return to normal levels on stopping. if, however, you are on a course for a couple of months that is less likely and the longer the course..the higher the risk that blood sugar will not return to normal just because you have stopped the drug. In your case, what is important- to know whether the drug caused (or triggered) the diabetes is a] how long did you take it for, and b] was your blood sugar tested at that time? Bottom line, anyone telling you that Prednisolone could not have caused it simply because you no longer take the drug is either needing to update their own knoweldge of that drug and its side effects, or they are avoiding the issue. Be very sure, a lot of diabetes nurses do NOT know the side effects of Prednisolone and most people they see will have diabetes due to lifestyle. Regardless of that fact...there is no excuse for them blaming you. Their job is to help, and that included motivating rather than the opposite. Further, even if your lifestyle did cause it - who makes all the grub full of carbohydrates? You? Me? Or big corporations that couldn't give a monkeys. Anyway - it's almost irrelevant what did cause it now, as is the attitude of an incompetent professional. All that count snow is how to ge tit lower..and that, my friend is down to diet...and when you succeed - you will feel pretty good about yourself. Focus on getting informed by people who count - other diabetics. This site is superb for that. Good luck.