I agree, it is exhausting. We do eat, sleep, drink, breathe SNs all the time... no break ever, even during a break we're still running things through our heads. I know it's not just me that does that. You can't shut it off from your brain...
I'm a SAHM, and I'm worn out from it all. I can't even imagine dealing with a full time job on top of it.
Some days I think life would be easier if we just HE'd and didn't have to deal with schools and statements and such. But then, we'd be HE'ding... LOL .... and stressed over that! Can't win! 
And a lot of us, I suspect, are caffeine addicts - coffee, tea, or diet coke - due to lack of sleep! God knows I am!
Anyone else have days where you'd just like to have a large bonfire with all the paperwork we're supposed to deal with?
I'll bring the hotdogs and marshmallows!!