By unnatural, I don't mean ungrammatical, but something people wouldn't really say. For example, in many fictions, you find yourself in very weird situations and it's hard to know how a person would react and what they would say in such situations. Often, I feel people would stay silent and say irrational or dumb things, but that cannot really happen, but often when you make your character say something relevant, it often sounds very unnatural and sometimes even cringy. Let me give you an example:
Natalia: You turned me into a monster, how could you do that to me?
Robert: It was the only choice! You think we could have survived otherwise? I made the call, because of that we're both alive. How can't you see this!?
Natalia: You made the choice without letting me decide my own fate. I cannot ever forgive you for this!
Robert: I don't care! Do as you want. If you want to die, go ahead, kill yourself. It's as simple as it gets. No matter what you tell me, it's not going to do any good. What's done is done!
Natalia: You pig!
As you can see, it kinda sounds awkward and ridiculous, but often it's not quite black and white, and it can be hard to tell especially if you've been writing a lot. So is there some kind of test or thought experiment you can use to make the determination that a dialogue is bad?
