Optionality has costs. If you live your life like it's going to go astray, then you miss out on a lot of the upside if it doesn't go astray (such as by being a stay at home mom, if that's what you actually want to do). The statistic that 50% of marriages end in divorce is often bandied about, but it also means that 50% don't. Which means that going all-in on your marriage is a completely reasonable thing to do.