Current cultural assumption is that your twenties are an extended adolescence where dating is to be casual/fun and you figure out what you want to do with your

Current cultural assumption is that your twenties are an extended adolescence where dating is to be casual/fun and you figure out what you want to do with your life, but your thirties is where all the adult stuff happens. I don't agree with that at all. If you want to be happily married with a family, you need to start moving toward that in your twenties in order to ensure you have a good chance of it. Fertility is not a given, nor do you know how long it will take to find a worthwhile partner. (I'm ignoring issues of kids vs career that women have to make here, which is a sucky thing indeed.)