I really think in a lot of cases people being bullied are just an added link in a chain of abuse. I think it's quite often the bullies themselves come from a dysfunctional home life. Either the parents, a new step parent, or an older sibling push them around.
As for how to deal with a bullying situation it's tough. I think often the victim feels the cards are stacked against them. They figure responding and fighting back will only get them detention. Or maybe the school listens, disciplines the bully, then the bully retaliates. At least these are typically the thoughts I had about the situation dealing with this nonsense.
It seems to me that people being bullied have to respond somehow even including violence(no weapons though just fists). It depends on age and size difference of course. Some fights are hopeless.
The bully is like the "Alpha" student though and needs to be challenged somehow. Possibly save up money and pay or bribe some jocks do beat down the bully if they're to strong for you.
Again though while I discuss use of violence somethings are out of line. Don't bring a knife or weapon that just takes this to an insane level.