"When are you going to have children?" That was one leveled at my uncle (just a bit older than me) and his wife repeatedly by meddling family members. What made it especially hurtful was that they had tried for over 10 years to have a child until they were successful. My wife and I decided 35 years ago not to have children, and we got hammered with the same crap. We are happy, and our career-choices over the years were made far more flexible because we only had to consider one another, not children. There were times when I worked brutal shifts, times when I spent weeks at a time away, consulting for clients 1000-2000 miles distant, etc. Our marriage remained (and remains) strong. We have always tried to give our friends and relatives breaks from their own children, so they could have weekends alone. We could grab a couple of nieces and nephews at a time and treat them to weekends of games, cookouts, movie rentals, etc, and have a great time with them.
We have extended that to the kids of a neighbor's daughter, in recent times. The girls are 4 and 6, and they love bugs, snakes, rocks, gardening, playing in the dirt, picking apples, etc. Their mother was divorced about a year ago, and moved back in with her parents with the kids. When my wife and I drop in, the kids run at us wanting hugs and bursting with news of what happened at school, and their mother and her parents do lots of stuff for us.