Bullying can cause some serious damage to a person, whether it is physical or psychological. It's wrong. However, something happens every now and then, and I hate to hear it.
When people try to justify the bullies.
They say that maybe they have problems in their family, they are frustrated, or whatever. I just have to say, NO MATTER HOW SCREWED UP THEY MIGHT BE, THEY'RE STILL HURTING PEOPLE. It's like the Sandman in the third Spiderman movie. Her daughter's dying, so it's totally ok to become a criminal and kill people and stuff, right? Nope. It's the same logic. HURTING OTHER PEOPLE ISN'T GOING TO HEAL YOU.
Unless you have the Blood Sword or somethingBullies deserve to be punished for what they do. Sure, maybe as little kids they don't realize all the bad things they're doing, but that's when the adults have to step in and talk about it. If the bullies are older, like I dunno, middle school-level and beyond, they know pretty damn well they're doing something considered wrong. But they keep doing it. And that might be for many reasons, but either way, they're being massive jerks. And that can't be tolerated.
If someone's bullying someone, sure, you report that and all, but considered how crappy school systems tend to be you are probably not going to get rid of them (unless you are in a school which is actually good in this aspect)... there's a number of things you can do: just avoid them, ignore them, stick with other people, and whatnot. Bullies always tend to hit in packs, so they are sure to "strike", so to speak, and so they have an "audience". And there you get the Bystander Effect. For some stupid reason there can be a lot of unrelated people witnessing someone being bullied and won't do crap. And that's stupid because all of these people could stop the bully, help the victim, or just freaking tell on the guy. And if you're being actively attacked by someone you have to get that point across. Get that kid expelled. You can't let yourself be hurt.
I would recommend to avoid fighting if possible (and if you don't know how. In that case, try landing a kick to the crotch. It works wonders

), but if you're getting attacked and you could get injured, you gotta defend yourself. Or if you're outnumbered, just run. And preferably run somewhere you can get help, not just some random place to hide.