Is jealousy common?

4 years ago, I had a crush on a guy I met through a religious event and I do not like him at all anymore but I was almost jealous when I saw a person who had the same last name as him on Facebook that shared mutual friends with me because I wondered if it was his wife, I later concluded they were probably not husband and wife since they were not friends with each other on Facebook. Is it normal to get jealous when your interested in other people with no relation to them?
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+1 y
It’s weird how these people do not know what my previous or current connection is with the guy and yet assume he is a stranger.
Is jealousy common?
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