I have three kids, two have diabetes. It gets really exhausting sometimes. My 10 year old is on a pump and sometimes I get so busy I forget to change her infusion set until bedtime. My 2 year old was diagnosed a year ago and is getting on a pump soon. I forget to write down there blood sugars alot and meal time is really stressful. My husband is gone alot with school so I am basically a single mom. I wish I could just go one day without the shots and finger pokes and carb counting. Maybe someday when we find a cure.
If you have or can afford meters that can download to a computer, one logistical edge I can recommend is using a meter for each child and doing the downloads/printouts weekly(ish)
More importantly - make sure you are taking the time to take care of yourself. In emergency situations it's an obvious notation. On airplanes, for instance - they tell parents to put their air masks out before assisting their children - because if you don't - the parent may not be conscious long enough after fussing with the child to be able to assist the kids on further steps... Self care is critical because of the responsibilities of caring for others that you are doing - and by the sounds of it - quite well - don't focus on every thing you miss - it's not a race, it's a marathon and staying focused and correcting for the misses is part of this. I've been living with type 1 for a while now and you are right, it is stressful - find a way to steal a little time (even if it's 10 minutes a day) for yourself - either hitting a punching bag, drinking a cup of tea, reading 2-10 pages of a book... something that you can say this - these 10 minutes are mine.
Okay- you may not have been looking for advice and here i am running on at the keys. I get the pressure - make sure you find an escape valve and for what it may or may not be worth - my read on the above leaves me with the impression that you are a remarkable mom doing an amazing job - so I'll ask ya' to try to abstain from beating yourself up during your moments of reflection.
Good luck and you've found a good place to vent - we do get it (at least some of it... of course - i'm a little slow... so maybe miss more than others...)