Morgan Housel is a wonderful writer and observer of personal finance. His book, The Psychology of Money, is a recommended read (I've given it to all my kids and is required reading for our new hires)!
Housel's recent blog post, The Art and Science of Spending Money, is an insightful look at all that goes into how we make decisions to spend money. While lots of people agonize and fret over investing money, few of us are as contemplative over how we spend it. It's a truism that one has far more control over one's spending than one's investment returns - yet we collectively spend far more time contemplating the latter than the former.
As I've aged I've become far more reflective over my spending - both large and small. I've become more willing to spend money on experiences, and far more discerning spending money on "stuff." I try to periodically review my spending - not just quantitatively (budget) but also qualitatively. My "best" (I define this as most bang for my buck) spending last year was on two family trips (Austin & Kiawah) and my worst was a pair of expensive athletic shoes that turned out to be neither comfortable nor durable.
Everyone's money journey is different - but being reflective about our spending probably deserves equal if not more attention than how our investment portfolio performs.