does bullies really feel guilty?

Whether in the school yard or workplace, all bullying seems to have a common trait—the use of power to hurt or humiliate another. In many cases the bully’s formative years are marred by poor parental example or by outright neglect. Many bullies come from homes where the parents are cold or uninvolved or have, in effect, taught their children to use rage and violence to handle problems. Children raised in such an environment may not see their own verbal attacks and physical aggression as bullying; they may even think that their behavior is normal and acceptable. If not stopped in childhood, they will likely grow up to bully others in the workplace. In fact, some studies reveal that those who had been bullies as children developed behavior patterns that endured into adult life. Sadly, bullies rarely recognize their impoliteness or apologize for their behavior.

when people can't control their own emotions they feel out of control. so then they try to control other people's emotions, through bullying, and this them a twisted sense of being in control. these types of people prey on those that are sensitive and easily affected.

sometimes this type of bully matures, and sees their past behavior for what it is. this happens to some people that bully, and they feel regret, though usually many years later

Doubtful. They end up becoming Liberals!

the only way to really win when bullied, is to stand up for yourself, once you do that, there is no need for the bully to continue to bully you.

A lot of bullies have been bullied themselves or they're insecure so they pick on others to try and make themselves feel better.

But no matter the cause, it's good to know how to handle yourself if you're being bullied.

What If I'm Being Bullied? :
https://www.jw.org/en/bible-teachings/family/teenagers/ask/being-bullied/#?insight[search_id]=240aff57-25fb-498e-aa95-d3e47c0f352d&insight[search_result_index]=2

read about karma
everything bad he did to you will return back to him
just forgive him and forgive the past and live your life ;)

Some do, some don't. Some only feel guilty years later when they've grown up a bit.
He hasn't "won". Bullies never "win". They are just insecure, angry and unhappy people. After all, no one who was happy and confident would make someone else's life hell! If anything, feel sorry for him.