Attending the Funeral of other Muslim after his death is obligatory on a Muslim and right of the person who is died. According to Sahih Hadith a Muslim have five rights on other Muslim in which attending the Funeral is also included. Attending Funeral of died person is actually a pray for him and when we attend Funeral of someone we are actually praying for him to Allah Swt.
These days Many People do un-Islamic things on deaths of others like shouting and hitting yourself that are completely Forbidden. On death of others we should do Patience and pray for the person who is died instead of doing un-Islamic acts. However the tears that comes in eyes on death of anyone are a natural thing. When we will attend Funeral of someone it increases the strength of relations between Momins and gives Patience to close relatives of died person. So we should always attend the Funeral of others and Pray for him. May Allah Swt help us to pray for those who are no more with us.