Why does almost everyone have secrets?

In my book, I can figure out a couple of reasons why people keep secrets?Perhaps the person does something wrong or stupid so that he dare not speak out ,fearing to be blamed or laughed at.At times, if the thing is very personal ,the person will also keep it as a secret to avoid embarassment.I guess some people want to share secrets with others ,but they just can't find a trustworthy one to listen to the secret.Also, people keep secrets because it's not right time to let people know.After some time, they will reveal what they conceal from others.

I am a person who can keep secrets for others as I  am not a bigmouth.If your secrets leak out ,you will probably feel betrayed.Why not keep a secret for others?For me ,most of time I only share secrets with the closest friend ,my sister or my mom,who will always stand behind me.As a result , there is no need to worry about secrets leaked out.

Is it necessary for us to confess everything to our boyfriend or girlfriend before or after getting married?

Last year, I read a novel called Tess.Tess is a beautiful ,and very nice girl who was born in a poor family.She was sent to work for one of her rich relatives who later raped her.After some ups and downs ,she found  her true love in a place which  was far away from Tess's hometown.Tess concealed her past from her boyfriend.They really loved each other that they decided to spend the rest of life as husband and wife.As the big day drew near, Tess was very antsy ,wondering whether it's allowable to keep her secret.As a reader, I supported Tess in zipping her lips about her past.At th same time , I was curious about the reaction of her boyfriend when he got to know the secret.The story was that Tess thought it was not totally royal to her to-be husband who meant her whole world so she chose to be frank to him.Then the story developed into a tragedy.

The unhappy ending shocked me a lot.It's when I thought it's not necessary to confess everything to our boyfriend/girlfriend.We should forsake our past ,especially a terrible past ,and give us a chance to secure what we deserve without hesitation.