I have the urge to insult other people.
Why would you do something as mean as making fun of others?
Would you like me to insult you?
I would rather you not. Even if you are having a had time or feeling bad about things, it is never ok to insult or belittle other people. It is better to find another outlet to make yourself feel better, such as talking things through, or taking up a hobby or exercising.
I can say whatever the fuck I want. I want to be an asshole.
If you act rude and mean to others, they wont want to associate with you. Also, having such a negative attitude will just make you feel worse overall. Instead, try to kind to others so you have a more fulfilling life with better friendships.