So, we had a discussion on 1st aid also involving CPR. Apparently mouth-to-mouth is also required where I live.

I tried to imagine such a situation, and over the course of around 8 hours spiralled into worse and worse thoughts as I kept overthinking every aspect of it more and more.
I'll try to just lay them into separate points:

1. I was thinking about how I'd approach the rescue breaths (mouth-to-mouth). I realized that this would likely end up being a problem for me. It would be hard to encourage myself into it, in the end wasting a lot of precious time letting the person's brain starve of oxygen. I don't know why, but this part feels very hard even to just imagine.
2. I started thinking of what if I was that person. Problem is, I would want to just die. This would be an opportunity without me having to do anything myself, and of course there would be no physical way to regret it.
3. What if that imaginary person would feel the same? (DNR doesn't exist where I live) I feel like forcing someone to live against their will is the worst thing I could do to someone.
4. What if I was actually causing more harm even physically? Combine the point 3 with hypoxia causing permanent brain damage. That would make matters even worse. I got to the conclusion that this point goes both ways, because it could also be caused by not doing CPR if the ambulance got there quick enough to still save the person, even if with severe brain damage at this point, as opposed to just permanent death.
5. Not being able to handle it, what if I tried to exit it by killing myself, perhaps by jumping under a truck? I felt like this would be most morally correct as it wouldn't leave me alive.
6. That could traumatize the driver or even escalate the existing accident.
7. At this point I was just exhausted, alternating between crying and feeling rage towards myself.
8. I took my dog for a walk which finally allowed me to calm myself down.

I don't know how I'd deal with this in reality. Of course I wouldn't have 8 hours to overthink everything.

Of course, this is just imagination with lots of overthinking, but I often spiral into thoughts like this. It feels like I am internally fighting myself about what's right and what isn't. Twice I got into such thoughts so much I couldn't physically stand until I calmed down at least a bit.