Hi Sam,
I hope you're on the mend now.
In my opinion, you're doctor is letting you down by telling you 7-8% is good I'm afraid.
The NHS set upper limit is 7%. The ADA has recently reduced it's upper level to 6.5%, and will go lower soon I hope. Healthy non-diabetics HbA1c will be somewhere in the mid to upper 4% range.
There's no reason not to aim for similar levels in my view, and quite a nubmber of forum members are certainly in the 5's now.
Your doctor will be aware that the UK avarage for diabetics is around 9%, so by that standard anything lower is good in a sense. But if 9% is double a non-diabetic level, it's not good in any real sense.
All the best,
fergus