I can empathize with your struggling with this issue. As a philosopher, I wrestle with this all the time.
There are many generalizations that you make, however, that I think deserve closer attention and scrutiny.
This issue is dependent upon many factors, only a few of which you discuss, e.g. one's attitude.
But socio-economic conditions, individual experience and its impact on self-image, gender, cultural attitudes toward particular individuals and their particular traits are just a few.
Individual ability and intentions alone do not make a successful individual. Nor do economic laws of supply and demand, or even darwinism apply to human life the way they do to economics or natural selection. Many dangerous ideas have been propagated along these lines, e.g. social darwinism of Spencer, National Socialism and other racist economic/social theories are a couple.
It really is a very complex issue and few philosophers have dealt with this in its entirety. In fact, only one comes to mind, namely Aristotle, who in his Nichomachean Ethics, discusses as many particulars as possible that must be considered.
As a final note, this is also a theological issue that varies with one's view of God.
I hope you take a look at Aristotle as it would make a nice launching point for a more vigorous analysis of this issue. And don't be put off by the fact that he wrote it 2500 years ago. The problem is that many haven't paid much attention to what he said.
(Mortimer Adler is a well known modern Aristotelian who has written some very readable Aristotelian positions and might be a friendlier approach. Six Great Ideas is one title that comes to mind that I would also highly recommend.