Champagne and other sparkling bottles are often made with a thin metal cage around the cork to prevent the pressure inside the bottle pushing up against the cork and making the bottles explode. Human emotions are similar to the pressure which can build up in a bottle, except we don't have the metal cage to indefinitely stop us from exploding, and eventually, with too much pressure and not enough release, the human mind will either explode, implode, or go rotten. It's important to release pressure in the mind, especially for men who are hardy or solitary. Catharsis doesn't necessecarily require another person to be present to hear the expression, only that the expression is made. Talking or even arguing with yourself, screaming in the woods or into your helmet on your motorbike on the highway are forms of catharsis.