Is it true the good die young?

My child was sick recently and with the recent H1N1 taking a toll, it worried me and started me along the road of maudlin thoughts and fears.

I knew 3 persons who had died around the age of 50. These persons were good people for various reasons – their attitudes to friends, colleagues and family. Why does God do that, especially when some of them had young children who would miss them terribly.
But when I look closer at each of these individuals, I realize they each had a greater depth to their inner being.

One lived quite selflessly first for his 5 younger siblings, he became a ‘mum’ of sorts when she died early; and then he lived selflessly for his 3 kids, keeping his troubles to himself always making others laugh. He died of a sudden heart failure (without prior illness) but he managed to speak to his wife in the last few minutes before he passed.
Another, was an uncle who prayed fervently, was active in church (like he was searching for something) and yet I knew even though he had a wife and child - was not happy. Yet he too showed us a happy face. The third was a colleague who was a very creative soul but had a little darkness to her character, which she displayed through dressing like Leticia (Adam’s family mother, always wore black lipstick) and was quite insightful in conversations with people around her. And she too was always smiling, joking, no matter how tough the work day was, never a melancholy sort in front of others.
If MJ’s death had not been how we know it now, he too would have fallen into this category, we know he was a persecuted soul yet he too had a different face for the world.

Is it that the heart gives out or the soul that has had enough or that Greater Goodness who decides that they have reached their limit of their human essence ? Someone once said they believed that some souls are temporary, are only on this earth to fulfill a higher purpose – to affect the lives of others.
How does one explain the passing of a young child. Why does God do that to mothers?