I believe the human brain is designed to feel anxiety, stress and discomfort as a survival mechanism initially, but as we in the West don't normally have to worry about basic survival any more the brain hasn't adapted accordingly.
Thousands of years ago we were in a state of semi permanent anguish over whether we or our dc were going to be mauled or worse by predators, whether there was enough food for our tribe , whether we had shelter and a place of safety.
It's no wonder anxiety is so common when taking a historical and anthroplogical perspective.
Finding peace with our lives, our own and our family's safety and happiness has always been a lifelong struggle for humans.
It is what makes us human.
Our minds are so powerful they can overrule rational thought.
The key is to harness our mental health towards positive life experiences rather than let negative life experiences over rule.
Basically, if we have a roof over our heads, our dc are safe, we have food on the table then we can must not take all that for granted, as there are sizeable chunks of human history when those things were an impossibility.
In short, we need to be kinder to ourselves and value safety and peace much more.
Everything else is secondary. We tend to lose sight of the basics because of cultural expectations and often unrealistic self inflicted pressures we put ourselves under.