I think you're just noticing it. When I was 17, Kurt Cobain died and it seemed overwhelming to me. Like nothing would ever be the same again. After he died, I noticed more people dying- like celebrities and people in my town. It was a long time before anyone I loved died, which is a different experience entirely.
I think it might help if you put it into perspective. If you suddenly started noticing how often people get promotions, it might seem like people are talking about it all the time and perhaps that it's easy for someone to get a promotion. Or if you noticed how often movie ideas are recycled. Or how often people get into auto accidents. Once you start noticing anything it seems frequent. I think if you put it into perspective, it might help you relax about the people dying thing. I hope you feel better about it soon, I'm sure that's a sucky thing to have in your head.