My own two cents is this: I dealt with bullies from a very young age, starting in elementary school. I took martial arts classes as a result. I never ended up getting in a fight or having to (ab)use these lessons against said bullies, likely due to an increase in self confidence. We both grew up, the bullying stopped, and I never encountered it even as I moved on to a different middle and high school, as I didn't present myself as a bully-able target.
Either that, or I was too weird and/or insane to bully in my later school years. But it was a comforting thought that I could quickly end a fight that was started with the intent of harming me then and there, on what basically amounted to muscle memory. Maybe that came from the confidence and self esteem, but it could've been a result of the crazy as well.
I honestly haven't thought much of the people who bullied me since, as I've since moved on and grown up enough to the point that I have more pressing concerns, such as whether or not to buy the Fallout 4 Collectors edition. Knowing what I do of this person, they are likely still in the tiny, dare I say podunk, town the elementary school was in, likely as a mechanic of some sort. I do not say this with malice, or much of any emotion really, as if that is what he wanted to do, he accomplished his dream separately, and we are different people from what we were then. Hell, we might even end up as friends, but it's unlikely that we would end up crossing paths.
The point of the above is this: Don't dwell on it, and move on, as unless you work or go to school with these people directly and on a daily basis there's little chance of encountering them as the years roll by. Find something that inspires your confidence and self-worth. Unfortunately, this will need to be done on your own or with the help of real life friends and family, as without knowing you personally I can't really recommend much. And don't just live for the revenge of rubbing it in their faces, live for yourself first and foremost. Living for revenge and anger, for striking back at the ones you perceive as wronging you, just makes for a toxic life that self perpetuates, and that's no way to live.