The idea of entropy absolutely can apply to human lives and destinies. You've got it backwards though: entropy increases through a human life. A simple and visible example is facial wrinkles. Young people's faces are more symmetric and smooth (less information, therefore less entropy). As they age, and life leaves its marks on their faces (ranging from getting your nose knocked crooked in a boxing match to developing uneven wrinkles), entropy increases.

The same applies to behavioral complexity too. Extremely young babies are either very predictable in simple ways, or very unpredictable in simple ways. Mature people exhibit a lot more ingrained, learned behavior. Thinking of all learning as algorithms, you can apply Kolmogorov-Chaitin entropy to their behavioral evolution... and conclude that entropy increases there as well.

This isn't a rigorous mathematical treatment. I believe one is possible (see an early start made by Chaitin in his paper "Towards a Mathematical Definition of Life").

There are aspects of this question that are somewhere between unclear to mysterious (to me at least), for example, applying entropy measures to the future "possible worlds" of an individual versus applying it to the past history. But basically the idea of applying entropy-thinking to human lives is a very solid one, even if we don't have all the mathematical details and answers yet.

I use this idea VERY extensively in a book I am writing, which I expect to publish early next year: http://ribbonfarm.com/tempo