A conversation in which people doubt things

Person:So, when I was a kid, they (dehumanized me in a fairly common and awful way).
Other person:Really?! They really did that?! I can't believe anyone would do that!
Person:...
Subtext:Wow, that is messed up, and I would like to make it clear that I think that is bad! It is bad! Not good! I do not approve! Don't think I approve!
Subtext:I've never heard of this before. I am shocked, shocked that this would happen, and I have trouble believing it.
Subtext:Are you sure?
Subtext:This can't possibly be common, this must be really unusual, this doesn't really happen.
Person thinking:Am I imagining this? Did this really happen? Is it really common? Why doesn't this person know this is a thing? Why doesn't anyone know this is a thing? Is it a thing?