When I was a financial planner I managed multi-million dollar portfolios for many clients, and my brand of planning was less about money-management and more about our relationship with money and how it ties into our lives and happiness.
So I got a chance to have some very in-depth and personal conversations with many a millionaire. Here’s what I learned:

Wealth is elusive; an unattainable goal. Most people who are rich don’t think they are. They - like many of us - said to themselves one day “when I have a million dollars, I’ll be rich”! And when they had a million dollars they realized they didn’t feel any different from the day before.
Some of them then said “when I have 10 million dollars, I’ll be rich”! And when they hit 10, it was just another day.
Eventually each one of them realized that numbers in bank accounts are inconsequential. Most of the millionaires I know are extremely humble about their wealth, because they know it doesn’t mean anything.
Sure - they may have more financial freedom than somebody working for minimum wage, but it doesn’t mean they have some secret sauce to life.

If somebody looks rich, they’re probably not a millionaire. All of the millionaires I knew and worked with lived relatively “middle class” lives. They drove second hand cars, or bought new and drove them into the ground. They didn’t flash wealth in any way.
According to the studies which produced the book The Millionaire Next Door, the people who look wealthy - living in mansions, driving luxury cars, and owning the latest/greatest toys - are usually way overextended financially, and most of their “wealth” is debt. Or - they’ve inherited their wealth, and will likely burn through it in their lifetimes without leaving anything significant to their children.
In fact, when I started in the financial planning business, I initially went after the people who looked wealthy, and discovered first-hand that they have outrageous amounts of debt and little if any savings. And they were a nightmare to work with in terms of implementing basic financial planning principles. Instead they were all bout getting another designer handbag.

Money doesn’t buy happiness. It’s an old adage for a reason: it’s correct. Studies were done on income levels and how they affect overall happiness. They showed that up to an income of $70,000/year, earning more does indeed correlate to better quality of life and happiness. But beyond $70,000/year, there’s no correlation. So just because somebody earns multiple 6-figure incomes doesn’t mean they’re happy. Check this out: Lifestyle Inflation: Why Earning More Money Sucks (the Life Outta You)
In fact, the more money you earn, the more you often end up spending, and the more stress you’re under to make ends meet. I’m considerably happier in my life now, earning $30k/year than I ever was earning $120k/year. Why? Because I’m doing what I really want to do in life - I put my happiness first, and found a career that could support it. I travel the world full-time; it’s a pretty delicious existence.