Do you think it's okay if I beat up a drunk guy?
What makes you want to beat up a drunk guy?
Because he fucked with me when I was drunk too
It can be difficult for people to control the actions they take when they are drunk. You shouldn't take advantage of others in this state. If someone hurt you when you were drunk, you should file a police report  and let the authorities handle it, this way you do not go to jail.
I'm going to break his jaw.
Breaking his jaw would be awful, and would certainly get you in big trouble. You shouldn't go around assaulting people who are drunk, even if they've done something to harm you.