Being married w/o kids allowed us to save big time. My $80K salary was completely saved, and his $26K salary was our living expenses. If we had waited to have kids a little bit, we would be in an even better position. But we knew we wanted kids and didn't want to put it off, and we certainly did not... we got married on January 8th and technically on January 9th, we were pregnant. I had a 3 month 100% paid maternity leave, so we had 1 solid year of dual incomes, which was nice.
Being married w/ kids, that's a different story. After our 1st was born, I spent a year at home and we lived on his modest income. We didn't save much, but with investment gains, our NW actually went up. Then I returned to work, and saving has begun again, but so have our living expenses. A 399 sqft apt. doesn't work so great for a family of 4, so we moved to a bigger place. Our living expenses have really gone up from the $26K we spent in 2008. We now spend about $42K, and only 8K is due to housing, so that means 8K is for other stuff that is costing us more... utilities have gone up, for sure (heat was included in our little apartment), inflation may play a small part. We definitely eat more w/ 2 additional heads in the house. Oh, preschool, that's $4-5K a year, and we have a few more years of that still. It's starting to make sense...
So, in summary, marriage helped, kids did not. Duh.