The mind is a fabrication of emotions, and emotions are naught but chemicals. Chemicals are defined as such by the mind. Where are we now?
This pointless, minuscule world known as Earth, inside a pointless, minuscule city, containing hundreds, thousands or millions of lives which will leave no lasting impact, passing away the same second they were born in the grand scheme of things.
And you? You're one of them. You have no power over anything. You will never be grand, president, ruler or king. Even if you were to be, what would you do? What COULD you do? Any action performed contributes very slightly to the heat-death of the universe. The more you act, the shorter the life span of the universe becomes. It is a paradox, unable to be solved. You are nothing.
If the universe would be scaled down to the Earth in size, you would be equal in size to a single electron, endlessly seeking significance and purpose. You are so horribly insignificant, yet anything you try to do will only shorten the existence of everything. Ending yourself is the best course of action you can do. It is the most unselfish act you can perform. Everything will exist a little longer if you do so. If you truly wish to prove your benevolence, suicide is the most impactful mark you can leave upon the universe, but even so, you will be forgotten completely, erased from time and space, remembered only by your relatives who will eventually pass away as well. So what will you do?