I don't know if it's a PTSD thing. It could be. But feeling nothing doesn't have to be a symptom of illness.
I believe that we naturally tend to feel compassion when the pain affects those we feel close to. From time to time, we'll feel moved by a more distant event. For me, that happens when the event resonates with my own mood. Extending compassion beyond that can be the result of a conscious work, as buddhists do for instance. It might be a natural thing for some people, but it seems to me those are quite rare -- I hope I'm wrong, here.
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Normally, when I hear sad or horrific news, I either feel nothing or I feel bad for a short while before the emotion retrieves. If the media make a big deal out of it, I will start to wonder why this horror gets attention and public display of emotions whereas so many others don't.
If I had been alone at home for the past two days, I suppose this is how I would feel about these murders.
But I haven't been alone in my bubble. I've seen friends and colleagues feeling genuinely stunned and sad. That's basically all they've had in mind for two days. Today was a national mourning day. A minute's silence was observed at work. So part of me got on board with this collective feeling of national tragedy. Just because it's contagious.
Still, part of me doesn't get it at all. How can my friends be so emotional about one tragedy, when they don't give a crap about so many others? How can their indignation be so specific? It makes me feel like I don't belong. And I wish I belonged more.
Not too deep down, another part of me finds it unfair... to me. If people can be so outraged and compassionate, why I am so lonely with my pain and personal tragedies? I am ashamed of this self-centred thought, but it's definitely there.