Existential questions

Sometimes I just don't understand:

-Why do people have to suffer?
-What is the meaning of life?
-Why do I get to live in a beautiful home when so many are homeless?
-How do I make my mom feel better?

They say life is short, so live every moment and tell those close to you that you love them. But if life is so short and temporary, and minuscule in the grand scheme of the entire universe, does it really matter if we tell people we love them or not, or whether or not we live our lives to the fullest?