When my husband and I were dating and applying to graduate schools, he got in and I did not. And, strangely enough, that was the best thing for us. We moved to buffalo with a very strict budget because we wanted to buy a house and take advantage of the 2009 tax credit. We had discovered that our mortgage would be about the same as rent, if we bought a duplex on my husband's salary. If we both had been working, maybe we would have bought a more expensive house, may not. Maybe I would have bought our house all on my own, (we were not married then) and DH would have paid off his debt quicker. But what I do know is that our budget would not have been so strict. We had $5/week each for fun money and date money of $10/week. Prior to moving to buffalo I had $20/week of fun money just for myself. If we had not had so little money to spend, we would have kept the fun money at such a high amount. But, because of our lack of money, we did not. And that means I am used to only going out to eat once a month, or waiting for a DVD of a movie or even finding deals to catch that movie we want to see in the theaters.
We also spent very little on groceries. We spent $30/week at the grocery store and $40/month at angel food ministries (which has since closed). That was it. It was not fun and the first thing we did when my husband got a raise was increase the food budget. But that means we know how to cut the grocery budget down and that has helped us, when we ran over budget during the first half of the year and now have to cut way down.
Those two are just small parts of our whole budget and we worked hard to be as frugal in every part. This meant that when our daughter was born, we could afford daycare while I went to graduate school for my Master's. It means that now, with my husband doing a post doctoral fellowship and me getting my PhD, paid, we can afford daycare and to save 30% for the future. We are a long way from saying 50%, which is our goal or financial independence which is my ultimate goal but learning to be frugal is the base in which all of this is possible. I never stop looking at our budget for leaks or trying to find better deals like geico affiliates or ting, both of which I learned about from http://www.mrmoneymustache.com/.