It is possible to change how you react to it.
Some things there is no changing. An unexpected death, cancer, a car breaking down - some of these things are just unforseen and cannot be changed. But how we react to them can be.
Then other things can be changed - we do proper maintenance on our cars - so there is less chance it will break down. We eat healthy and exercise, so it is less likely we will have heart disease or high blood pressure.
It is about taking control of what we can, and being able to bend and adjust when we can't control things.
This is why control freaks have heart attacks so often - they can't "bend" when something falls outside of their control.
To be healthy we have to be able to recognize and do both.