Unless you're really rich, you probably don't just buy cars for fun. Cars are expensive to obtain, insure, and maintain. They are expensive to run, and usually, if you're going somewhere in a car, you're going someplace you're going to spend money.
When you have a family to consider, your priorities around your transportation will change. A young bachelor might prefer a two-seater, but give that man a wife and two kids and suddenly, that little sports car seems ridiculous. A car itself is just the beginning. Just as a home can be chosen for purposes of raising a family or a back yard can be prepared to keep toddlers safe, the things with which you fill your home, your pockets, or your car, reflect what you expect to use it for, and what hopes and fears you have for yourself and your family.
As life goes on, you may improve your knowledge base by making mistakes, or learning from others. If you worry about asthma, you'll prepare differently than if you're worried about obesity, or bullying, or any of the other things married folks consider when they plan for the future.
So think about how you set up your life, your car, and your marriage, and we'll tell you how long you've been wed!