Broken Pencil

Listen here, you obviously don't understand humor. A pencil is something that people use to write and when it is broken, it does not fulfill it's purpose. You are saying that your life is like a broken pencil, because your life does not fulfill it's purpose. In addition, you are using the word pointless as a pun, since a pencil has a point. In this case, 'pointless' also means 'without purpose.'