Why?

..Why do people think that their life is not worth living?...I have no clue why we should actually convey everything SAD and not so going well with our life everyday when we actually have something good happens?Do we need the attention so that people will respond to our sadness with something like 'Oh.so sad.i hope you are fine' or 'What's happening?Do you need someone to talk to?' If everyday and everything in your life or even your blog is something emotional,sad and etc it shows that the person writing has nothing to do in their life and just blabbering about his/her sadness.It's sad,for people like this.and for me as a blogger,i will never visit that kinda blog ever again.because i don't want to start/end my life with sadness by just reading those emotional writings of yours....