Spotted this on my Facebook feed, and it turns out to be a really old article, 2007 vintage. First time I've seen it but did make me laugh and certainly resonated, and it's just the sort of answer that my missus would fire back, especially if I asked that fatal question... what have you been doing today? 
Article from the Washington Post, 2007, by By Carolyn Hax
Question:
Best friend has child. Her: exhausted, busy, no time for self, no time for me, etc. Me (no kids): Wow. Sorry. What'd you do today? Her: Park, play group . . .
Okay. I've done Internet searches, I've talked to parents. I don't get it. What do stay-at-home moms do all day? Please no lists of library, grocery store, dry cleaners . . . I do all those things, too, and I don't do them EVERY DAY. I guess what I'm asking is: What is a typical day and why don't moms have time for a call or e-mail? I work and am away from home nine hours a day (plus a few late work events) and I manage to get it all done. I'm feeling like the kid is an excuse to relax and enjoy -- not a bad thing at all -- but if so, why won't my friend tell me the truth? Is this a peeing contest ("My life is so much harder than yours")? What's the deal? I've got friends with and without kids and all us child-free folks get the same story and have the same questions.
Answer:
Relax and enjoy. You're funny.
Or you're lying about having friends with kids.
Or you're taking them at their word that they actually have kids, because you haven't personally been in the same room with them.
Internet searches?
I keep wavering between giving you a straight answer and giving my forehead some keyboard. To claim you want to understand, while in the same breath implying that the only logical conclusions are that your mom-friends are either lying or competing with you, is disingenuous indeed.
So, since it's validation you seem to want, the real answer is what you get. In list form. When you have young kids, your typical day is: constant attention, from getting them out of bed, fed, clean, dressed; to keeping them out of harm's way; to answering their coos, cries, questions; to having two arms and carrying one kid, one set of car keys, and supplies for even the quickest trips, including the latest-to-be-declared-essential piece of molded plastic gear; to keeping them from unshelving books at the library; to enforcing rest times; to staying one step ahead of them lest they get too hungry, tired or bored, any one of which produces the kind of checkout-line screaming that gets the checkout line shaking its head.
It's needing 45 minutes to do what takes others 15.
It's constant vigilance, constant touch, constant use of your voice, constant relegation of your needs to the second tier.
It's constant scrutiny and second-guessing from family and friends, well-meaning and otherwise. It's resisting constant temptation to seek short-term relief at everyone's long-term expense.
It's doing all this while concurrently teaching virtually everything -- language, manners, safety, resourcefulness, discipline, curiosity, creativity. Empathy. Everything.
It's also a choice, yes. And a joy. But if you spent all day, every day, with this brand of joy, and then, when you got your first 10 minutes to yourself, wanted to be alone with your thoughts instead of calling a good friend, a good friend wouldn't judge you, complain about you to mutual friends, or marvel how much more productively she uses her time. Either make a sincere effort to understand or keep your snit to yourself.
It does sound very familiar, needing 45 minutes (or more!) to do something that takes 15 
Michael MacIntyre does some great sketches about having kids as well. Explaining the mechanics of leaving the house, without kids, you put your shoes on, open the door and walk through. With kids its a military operation, with one kid taking clothes off while you are trying to put a coat on the other 
I reckon stay at home parents should be entitled to some kind of award, or maybe a state benefit of an all expenses cruise round the world when the kids leave home 
