Hi,
Unfortunately there are many myths about diabetes, and like you said before you was diagnosed you probably knew very little too, i certainly didn't know much either!
But saying that, with knowledge or not, a little bit of tact wouldn't go a miss.
I hope you corrected this mistake in thinking it's because 'you didn't eat breakfast' I know it probably took your by surprise and you probably felt quite embarrassed but until corrected they won't know any different, and as friends they should intently listen to the facts about diabetes!
It's very easy to slip up especially when you feel angry and upset, i myself try to eat healthily although i wouldn't consider myself on a diet.
Of course i use insulin as a T1 so i can easily correct high BG's but the more insulin you use the more likely you are to put on weight so i still have to think a little when i'm eating. Coming into bikini season and i have a bit of a tum, so having choccies and things i tend to feel a little guilty!
You can't reverse what you ate or anything, so there's no point beating yourself up about it. All that matters is that you forgive yourself, accept that your human and everyone slips up and get back on that wagon!
I think getting back on the wagon after a slip up takes more courage than it does to start it, it's easy to think well i've messed up so whats the point. You did it before so you can do it again!
Someone once said to me 'is it because you ate too much sugar' My reply was a stright foward 'no not at all' and i explained what Type 1 diabetes is, after this the person thanked me for setting them straight, apologised and was genuinely happy to be 'in the know'
Another person said, oh my mum has T2 diabetes you have the bad one dont you' to which my reply was 'i have a different type of diabetes, but that doesn't mean one is as bad as the other, they're both illnesses and deserve the same respect' This person was also quite happy to be informed that, and i was also happy to know i'd set the record straight one person at a time so next time they come across someone with diabetes then they will know better which in turn will help the person with diabetes as i understand it's embarrassing to 'correct' someone, but i'm afraid it needs to be done. You may find your friends will be more understanding once they know more about diabetes.
I have a friend who has a heart of gold and purposely drinks diet coke when i'm around and will make certain choices that i would like declining a pudding. i know it's because i once told her i was upset that alot of people could eat alot more than i could without thinking when i was first diagnosed. I don't think she thinks i know what she's doing but it touches me to know that she has these little thoughts bless her heart. She also asks me 'where you at?' which i know means whats your BG level? But if i'd never said that to her in the beginning maybe she wouldn't be so caring now?
Hope you feel better about it, climb back on the wagon as Diane brilliantly said 'keep your chin up, this is a marathon not a sprint.'