Hi Susie!
BG meters can read a bit high or a bit low, but not by the margin you're seeing. They can be up to 20% out and are more likely to be so when you're out of range e.g. very high or very low. However, this would not account for the numbers you're consistently seeing.
I haven't seen your other thread, so I don't know who is advising what, but HbA1cs can also be wrong. Often when you have certain blood conditions they can be wrong. For example, anaemia can give a falsely low HbA1c. Is it possible your 8ish HbA1c was a result of another medical condition and didn't truly represent your levels? There is another test called a fructosamine test that they can do if there is a suspicion that your HbA1c is wrong - I had one just recently as a consultant had called into question my HbA1c - in my case, the fructosamine simply confirmed the HbA1c result as genuine.
Spiker's concerns for you are very real. Insulin is critical to your health, and not just for reducing your BG. You will see many posts from Type 1s talking abouot a fear of DKA. It is a condition that can come on rapidly and is generally caused by high BG and insufficient insulin. By high BG, I mean anything over about 13. I would treat BGs above 13 with rapid-acting insulin and test for ketones. DKA can kill you within hours. The levels you are running, if anything like accurate are not just damaging long-term, but can cause sudden and catastrophic events too - DKA, Heart attack, stroke. This is why you need to see someone with appropriate expertise quickly. Your doctor sounds to me like he is not equipped to deal with this - as well-meaning as he might be, when he saw those levels on your meter, he should have sent you to your local diabetes hospital immediately - especially with your other health issues.
Smidge