Why are some people so over-emotional?

I'm talking about people who cry when watching a movie and who explode in anger at the slightest disagreement. How do you even find justification for tears to start flowing?

A movie is a piece of fiction. It's fake. It can be immersive, but we all know that none of the content is real at the end of the day.

When the other side disagrees with you on a certain topic, why would you take it personally? They said nothing about you, only the subject of debate. How does one even interpret it as a personal attack??

How do some people even manage to convince themselves to cry over these things? There are some things that are worth crying over, but some people seem to actively look for excuses to cry. What's up with them?