Celebrity deaths don't affect me much
I think we could simplify this by saying to mourn you need an "emotional link" to the departed. Therefore people who "swooned" when they listened to Elvis sing, shouldn't have seemed odd when they cried when he died.
Similarly I felt sad when Martin, John, and Robert (and many others) died because of my attachments to them.
But I've never felt that strongly about any other entertainment type celebrity's death (except I'm still upset about John L).
Until this Christmas I would have said exactly the same as most people here - celebrity deaths don't affect me that much. I think generally that's still true, but I do feel kind of blown away by Carrie Fisher's death. She seemed to grow up from the immortal Pricess Leia into this beautiful, funny, straight talking woman. I loved her performance in The Force Awakens, I though she looked beautiful. I am really cut up inside that she's gone. Maybe it's because Star Wars was my first and most lasting special interest and she was, for me, the best of the original cast. To me it feels like a death in the family. She has been a presence in my life for thirty nine years.
I do think these feelings I have are strange because how can I feel like this for someone I never even met? I just wish she was still here.
Maybe this is the odd thing about celebrities - they are known by us and we know a lot about them - more than we might know about our next door neighbour for instance - and yet they don't know us at all. It is the psychological illusion of a relationship. However, illusion or not, it can still light up the same grief circuits in someone's brain if enough connections are related to that person.
Just my thoughts...

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I do think these feelings I have are strange because how can I feel like this for someone I never even met? I just wish she was still here.
Maybe this is the odd thing about celebrities - they are known by us and we know a lot about them - more than we might know about our next door neighbour for instance - and yet they don't know us at all. It is the psychological illusion of a relationship. However, illusion or not, it can still light up the same grief circuits in someone's brain if enough connections are related to that person.
Just my thoughts...

You said:
Let's look closer. Suppose for a minute you had met this person (????).... exactly what difference do you think this might have made? From my point of view it wouldn't make any difference unless I was so smitten before the meeting that I would be totally overcome....except that I don't get "smitten" by any celebrities. Perhaps some do...I'd imagine many lonely people, looking at celebrity's exciting lives, might wish they could have a special friend like that to fill the emptiness inside?
And if people can fantasize about celebrities this can form emotional bonds (even though they're only one-way) which lead to human emotion regarding that person. The main thought is how strong the emotional bond has become. For many this may be the only strong emotional bond in their lives so a strong emotional response at this person's death would naturally cause emotional upset.
My dad has a story about this, from when Princess Diana died. I remember there was a nation-wide state of mourning that went on for months, you couldn't get away from it. A woman at work said to him: "There must be something wrong with me. I don't feel sad that she's dead." He replied, "That makes much more sense to me than getting all upset about someone you've never met and don't really care about."
I've got the same attitude, and the Diana thing freaked me out it was so disproportionate. I was at my girlfriend's house, and her mother and aunt were watching the funeral, which they'd videoed. Something about the way they were watching it made me panic so much I fled the house, going the wrong way down the street so I didn't have to pass the living-room window!
The only celebrity deaths I've really grieved over (in moderation) were two writers: Iain Banks and Terry Pratchett. I think it's because I felt I knew them from spending so much time in their books. I like Star Wars, and guess I "should" be grieving for Carrie Fisher. While I do see her death as something sad, it hasn't hit me that hard somehow.
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