I know this is going to be upsetting for some of you to hear, but after a certain age you are not supposed to physically fight people anymore.
I'd say the cut-off age is 18. Maybe, with some slack, 20.
After that, you handle things either with your words, or with non-fighting actions, or by using the legal system.
You don't fight them.
(I'm going to repeat it one more time for all the Long Island lesbians: After you become an adult, or the age where most other people become adults, YOU ARE NOT SUPPOSED TO FIGHT ANYONE ANYMORE. Just because you look like a 15 year old boy doesn't mean you should act like one.)
If you have any questions or concerns, please feel free to comment.
Love, Juliet