I recently had an existential crisis. It was awful
Oh no.  What happened?
I watched the new Avengers movie and a lot of people die. And I realized we're all going to die and there's no way to know what that's like. And then I felt sick for a couple days and couldn't stop thinking about it
Wow.  It had that much of an effect on you?  That it made you consider your own mortality?
Yea. I don't know why, it was the dumbest thing. I was really upset.
Well it's good to remember your mortality, even if you have to ignore it to continue normal life.