Libertarianism and Communism share a common flaw

[Deus Naturae]

SPC has it right. On top of what he said, I'd add that there are some people who are prone to making bad decisions, but insulating them from the consequences of these decisions only serves to aggravate the prevalence of poor decision-making. In the words of Herbert Spencer, "The ultimate result of shielding men from the effects of folly, is to fill the world with fools."

[Deus Naturae]

Monarch, I think you are strawmanning libertarians. We don't oppose voluntary cooperation between individuals or claim that everyone is purely selfish (though in your financial advisor example, both parties are acting in self-interest; their interests are simply aligned). What libertarians oppose is government interference with precisely this kind of voluntary, mutually beneficial relationship.

Also, individuals who delegate certain parts of their lives to other parties do so because they, as individuals, have decided that they that aspect of their life is better managed by others. Contrast this to the government which decides it knows how to manage people's lives better whether they agree or not.