I’ve been extremely lucky moving to the Bay Area to be someone who has not failed. I grew up poor. Today, I have enough money for rent and bills, I still think and worry about them. The endless what if’s are a lifetime long curse, and there is no cure.
No, it's that you don't have enough margin (possibly because your lifestyle expanded to keep pace with your resources?)
My parents died. They'd been sitting on property and had never tried to 'featherbed' their kids' experience, so we all grew up THINKING total failure was an option. I survived until I was over 50, very much living constantly with less than $1000 in the bank and a roof over my head (one exception to the latter, but it didn't last long)
I went, at a stroke, from that, to more than $100k in the bank (quite a bit has now been turned into equipment for my work, but not all)
If you have enough money to go for a YEAR with everything else collapsed and gone to zero… as in, however lush or humble your lifestyle, you lose all means of income, but it'll taka a year for you to burn through all your money and have none left… and then you have not lost your normal income after all… that would probably shut off the 'what ifs'.
It's a margin thing. You can continue to keep track, you can continue to fill out your checkbook and all that, but if your margin is roughly a year before you're in serious danger then you will probably not burn extra cycles worrying about your finances. And if you do, the therapy to straighten that out won't be super hard.
I bet you 'enough money for rent and bills' means you can always pay them, not that you've got 12 times that amount socked away. I absolutely wouldn't have ever had that except that my parents literally died and left it to me. I don't design my life to squirrel away 12x more money than I will ever need. I think it's unhealthy, though obviously my folks did something of that nature to create the situation.
Mindfulness, treatment/therapy, etc. can go a really, really long way though. Speaking as someone who’s been there.
Investing in yourself is absolutely key. It’s something most folks from our background have been taught to not even attempt. Not doing it just reinforces the cycle.