Cut yourself some slack

So lately I've been running on little food, even less sleep, and no fun! Between a two year-old (and yes, I know no one believes that sweet Lucy could ever be a "terrible two", but she is) and a baby, working full-time, learning the ropes of my new promotion, keeping the house clean and stocked, cooking, and training for a race...I just don't have a second to spare.
I kind of reached a breaking point last night. During my run my legs and arms were shaking like crazy. I kept going, telling myself I could just push through it. But each lap only got harder, and I never reached the "second wind". I was so disappointed in myself I almost started crying.
Then it hit me like a ton of bricks how silly I was being. Of course my body was giving out; I'm making all these demands of it, and giving it nothing in return!
So to all you "super moms" out there, trying to create this perfect life for yourselves and your family: don't. It's not possible, and you're just making yourself miserable trying. Juggle what you can, be great at a few things...but don't try to outdo yourself at everything all at once. It's not worth it!
Just be happy. That's what will make your family's life the best, anyway. Be happy, and give yourself a break!