I married a frugal man.
Darn it, you beat me to it. Marrying my wife was a hugely positive decision, financial and otherwise. We help each other be financially wise.
What else would I put on the list?
--Career choice
--Modest first home
--Scholarships and working during college
--Learning to DIY just about everything
--Consistently resisting lifestyle inflation
--Investments on autopilot
--Developing technical skills beyond my primary job responsibilities
--Making myself super valuable at work so that when I threatened to leave, they bent over backwards (financially) to keep me
I've also benefited from a lot of good luck--parents who prioritized education and hard work, a natural curiosity, grandparents who helped fund college, buying our current house near the bottom of the GFC, having the right skills at the right time when my employer launched a new venture, good health, etc.