Oh my. What a lot you've had to deal with.
I can't really express how sorry I feel for you having to deal with all of this. Communication is so critical in all things healthcare, and yet sometimes it is so poor. Of course, as a patient, I can be equally bad at expressing myself well; especially when emotions are running high.
One point I will make though is that I detest the use of the phrase "poorly controlled diabetes". It means so much, with so many meanings to so many people. It is my belief though that when a Doctor uses that term, they don't necessarily mean the patient has been careless or,negligent in any way, the mean that for whatever reason the bloods have not always been bang on optimal range. I can recall a discussion about that some time ago, when this came up.
I have to admit, I was quite surprised by that commonly accepted definition, because, like you, I would have taken it to be a personal slight. Min an emotional state,I would have taken it as a devastating body blow.
Why not ask whomever wrote to report to define the statement for you. It might help clarify whether that is something specific to be addressed in any complaint you consider making or whether it is a hugely unfortunate use of a potentially misleading and unfortunate phrase.
I do hope you and your family can begin to look forward to better times soon, because there will be better times when you,can all be happy again.