Aw, honey. You're not alone. I'm managing my son's diabetes and I know the feeling -- I get so bummed out if I make a mistake or want to roll over and get more sleep instead of check his BG, but knowing that if he's really high or (worse) really low, I'll never forgive myself if I don't do it -- the idea that he could be harmed if I slack off usually gets me motivated. I suspect that where your parents are concerned, they ride you because they're so afraid that if you're NOT perfect, they'll lose you to this ****ing disease, but they also know that they can't do it for you. Hovering is just SO annoying, I know, but look at it from their perspective -- you're precious to them, and they think that even the slightest error could cost them their beloved daughter, so of course they're going to get on you when you make mistakes. To make a long story short, they're just plain scared, so they fuss.
I can relate to them because I'm a parent of a child with diabetes, and also of a teenage girl, though the two aren't the same kid. So believe me when I tell you that deep down, they don't want you to be a perfect little diabetic. If they had their way, you wouldn't have diabetes at all (BTW I hate calling people diabetics. A person isn't a disease, and the disease doesn't define the person. Remember that.) But they can't have their way, and that probably drives them bananas. What they really want is for you to be as responsible and mindful of your diabetes as they would be if they were in charge of it... and that's ridiculous, because you're not an adult and there's not a person on this planet who is as responsible for his or her own health as a concerned parent would be.
Do the best you can, Brandi -- that's all any of us can do, adult or otherwise.