There is a theory about this idea of communal emotional and spiritual development in the Australian Indigenous culture (Australian Aboriginals), as well as in the Islamic faith. The idea that for one person to be truly happy they must strive for the benefit of all others in their community. In a way, it's the most positive reincarnation of Nietszche's will-to-power and showcases the wisdom of communal ethics.
I really believe in trying to bring others UP rather than DOWN. I try to accomplish this, I often fail. But I'm trying, and I'm trying to spread the message. And that's the point isn't it, to do our best with the tricky language and less than ideal life factors we have.
In short, the whole idea is that to be happier within ourselves, to be more peaceful and less concerned with the doings of others it's better to wish them the best, to encourage them to succeed and do their best in life because it makes us better people. When others succeed they want us to succeed and vice versa. It's a way in which we can create the philosophic ideal of Eudaemonia within ourselves and then pass that onto others.
Here are some fantastic videos which probably explain this better than I can: