Why in general Americans are so selfish that they do not keep in touch with parents and siblings after moving out and don't help them when they need help and only focus on their romantic relationship?

This question is based on an inaccurate assessment of "Americans in general." Plenty of American families have tight family bonds. Also many American families have strains of resentment between members.

Your relationship is what you build and also is what you were taught.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.