Thank you, it was informative

I looked it up... I don't think I have this though, I'm not sure if it's learned, but I can identify emotions in myself and others. While I might not be able to describe it in human words as they're image based, I usually know how others might feel in a situation too. Now, whether I feel anything for those humans expressing something, that's a whole another matter, I'm pretty emotion-detached, if I'm offering emotional help, it's usually from a practical and logical place, but with understanding of how they might be feeling. Empathetic, but not sympathetic, as it were.
Having said that, I can see how it could relate to the observation in the original post - as one would need to know what it feels like to miss someone to give weight to someone else missing them. But then comes the depressive thought - am I even worth missing at all? - so I shut that possibility out completely. I think, I'm more in line with
@Bella Pines, in that, people have their category box of where they belong and it's sort of a way of coping, to detach and make people vanish from thoughts not to replay embarrassment, mistakes, or anything else.