I have a concrete example that involves literally slamming a door. In fact, I may be the origin of this expression in typology communities.
Once, when I was younger, I found out that my best friend was moving away. I begged them not to, and when they said they couldn't help it, I angrily told them to leave and never come back because they weren't my friend anymore (thinking that if they really cared, they wouldn't leave, and thus they must have been tricking me this whole time by pretending to be my friend). The next day when they came over to say goodbye, I slammed the door in their face after saying in an mildly bored voice, "Look, I already told you, I don't like you anymore. Bye."
And then I just walked back over to my computer and started working again as if nothing had happened. My mother remembers this because she said it was the "coldest thing she'd ever seen." And I do feel more shame about it now, but I think I just felt that once I ended my friendship, it was over, and that was that. I still kind of have that mentality, but I understand that it's messier than that now for a lot of people, and try to be more accommodating, but my heart's not in it at all once I end the friendship. It's more like realizing an obligation to tie up loose ends properly, rather than caring about them at that point. A weird trait... it makes me wonder if something is wrong with me at times.