I could afford it either, but I did it anyway. You really can learn to live cheaper. And by cheap, I'm talking shoe-string. It CAN be done.
We afforded it and we were as poor as church-mice. Home-canned fruits and vegetables go a long way. Also, a take-out burger back then was a real TREAT.
She didn't need to buy or care for work clothes. She didn't burn nearly as much gas. She loves to cook, and suddenly had the time, so we didn't eat/order out nearly as often.
Don't get me started on marginal tax rates...
Projecting ahead to daycare costs, we could see that we wouldn't be that far ahead if she did go back to work.
Which she didn't want to do anyway. Still homeschooling our ten year old!