I wasn't bullied until my senior year of high school, but man, was it intense. It was all psychological, not physical, but it was bad. Thank heavens it was all before facebook or my space! My mom even considered sending me to live with my older sister and finish high school in another city, it got so bad. My parents stayed on top of it as much as they could. The sad part was that some of my friends didn't want to "choose sides," even though I didn't start the conflict. One friend overheard some of the brunt of it and was so appalled, he did become a staunch supporter. I mostly ignored it to the extent I could, and when I struck back, it was sweet. (I got the bully's dream date to our homecoming dance, which intensified the bullying afterwards, but oh, was it worth it--he was a really nice guy and I felt a bit bad for asking him to take me to homecoming as a means of getting back at her, but he and I did have a lot of fun at the dance since we were just there as friends.)
Anyway, I still remember it and I guess you could say that there are scars. However, I'm living a great life now, and I think the bully is, too. I know for a fact that she didn't get some of the high school honors she wanted because the teachers were so annoyed by her campaign of harassment against me. One of them told my mom that directly. It's like another teacher said below--there are acts below the radar that they can't necessarily combat, but that doesn't mean they don't know what's going on.
My niece was bullied more directly with threatening texts, so my brother was able to copy those and take them to the school and show them to the principal. He also called the parents of the other girls and told them that if his daughter showed up with so much as a scratch on her (because the threats were physical in nature), he would press charges against their kids with their own texts being evidence. That ended the problem instantly.
Anyway, this is long, but I promise you I keep a close eye on my child for signs of bullying and I will absolutely step in if I ever have to.