One day, her husband walks in on her lover and her in the middle of one of their trysts, and he sues her for divorce. Her marriage is over, and one should certainly consider it a failure. Again, common sense states the latter would be the better path to choose. Howard suggests that laughter is one of the most healthy things a person can do. He is not wrong.
Laughter obviously relieves stress and enhances relaxation.
This effect is probably because laughter is a natural relex to an enjoyable situation. Sure, some people also laugh or giggle at times of extreme embarrassement or nervousness, but once again this is usually an unintentional reflex to the situation. In both cases, it should come as no surprise that the act of laughing is having a positive effect on the body. That is why the reflex exists. Once again, Howard has managed to make a broad generalization that is not only incorrect but potentially unhealthy.