Are you possessive over specific people?

I have seen some people get very thrilled if a mutual friend prefers them to someone else , a father or mother favouring them over others and so on.Soemtimes it can evn become an obsession leading to dire results.Is this a common characteristic?As far as I am concerned I have not felt that way.People will have their preferences and it is the way of life.As long as we are able to get along with everyone, it is enough.What do you think?