What is one of the most difficult moral dilemmas you've ever faced?

What is the first thing that comes to your mind upon reading this question? Please do not look at the details unless you are absolutely stumped for what to think about.

Maybe you’ve faced an unwanted pregnancy. Maybe you’ve had to struggle with a decision to implement a DNR request. Maybe a boss has asked you to do something unethical or illegal, and you are desperate for an income. Maybe you weren’t sure something was illegal, and you deliberately didn’t try to find out. Maybe you had to decide whether to look the other way or not.

These are just a few examples I can think of. I hope there are situations I can’t even begin to imagine. Pretending I didn’t prejudice you with my examples, what was one of the most difficult moral dilemmas you’ve ever faced?