What’s the hardest decision you’ve ever had to make? Why?
In retrospect it is difficult to retroactively reflect accurately on this question.
As we get older we have more experience to make decisions and we make decisions earlier without the luxury of even a fully developed brain.
I remember driving to Virginia with a moving truck which I barely knew how to drive. Decisions were easy back then as you had nobody depended on your decision.
I have always been a go with the flow person.
Most difficult
Are probably the decisions that are made for you. I recently got laid off from a job which expedited the decision to retire.
In my practice marriage, my partner decided she wanted a divorce. Those decisions are difficult but we figure it out.
The Side Effects of Endorphins 
I would love to hear you opinion as well