Tang Yin, a Chinese poet from Ming dynasty, once wrote:
People live a lifetime of 70 years,
In the first decade, we are no more than a child,
In the last decade, we become feeble and old.
With just fifty years in between, we spend half sleeping.
In his book The Expression of the Emotions in Man and Animals, Charles Darwin wrote that most emotions bear purposes. Therefore they are products of natural selection. In a primitive tribe, anger, which seems negative and harmful in common sense, keeps one being feared by others and helps establish authority.
There are always ups and downs as a relationship moves forward. In the process, you will discover more about your partner, and surprisingly, more about yourself. Many people tend to think that they have a good personality and sense of reason until their understanding of themselves is shattered after a relationship.