Humans would not survive in the wild alone -- imagine trying to fend off a wild beast with a stick by yourself -- so they feel a negative signal when they are disconnected from others, Cacioppo said.

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To protect yourself, stick with those listed BDCs that came through the financial crisis relatively unscathed.

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And tell yourself you must stick with the list.

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The more you stick to your morals and ethics and surround yourself with people who share similar beliefs, the happier you will be.

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