Except they could not. You can't buy with money the experience of a good life partner, you cannot buy with money the experience of having kids and raising them.
Those are things you buy with your time, your life clock if you will. You have a limited budget of time and you don't get to spend it twice. And when you get to the point where you feel like you've probably spent half or more of it, you might look at what you spent your time acquiring and be disappointed.
Pretty much everyone I've talked to about 'success' uses the definition of 'the sense of pride in what they have achieved in their life so far.'
If the value of what is a 'good' thing to achieve came from inside of you, then in my experience, you'll be happy with what you've achieved. However, if you adopted someone else's definition of what is 'good' to achieve, you may find that having achieved it you don't feel happy. I expect it is different for everyone.
What this conversation did for me was to show me how one thought about 'success' affected the choices of where you spent your time, that they were different for everyone, and that people using someone else's idea of success could be disappointed or unhappy having achieved 'success'. And that realization helped me make decisions about how I spent my time based on what I valued in my life rather than by an arbitrary "score" like a bank balance.
The different between you two though is that they have millions and can still have your lifestyle within a couple of years.