A profound wisdom is evident in your essay Elena.
With your permission, let me clean up the grammar just a bit, and then discuss this wonderful insight that you share.
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About the friend
To my mind there aren't real friends.
You may communicate very WELL while your interests are different;
but when you need in help, there aren't friends."
"Though... No, you'll get your friend's help; but when you achieve success, that's the end of the friendship. That's all. That will be the end of friendship."
.
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"People like pitying friends, but they may not be happy for them. I think that you know people first of all when you are happy. You are lucky if your friend hasn't got an envy. As for me I have many very good and familiar acquaintances, but I haven't any real or true friends, And it suits me."
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Awesome human insight Elena. Very deep thought and I would indicate that Ego-Centrism is the general English term for the subject that you address here.
This is wonderful. You could write more on this in the future I am sure.
This is powerful exploration of human psychology and Self-Centeredness.
It is most commendable!
----Warm Regards, Bruce