I am in agreement with others above, this is something you need to tackle with a therapist. It isn't trivial, nor should it be treated as such.
Some people who bullied....they really lack the capacity to empathize. It sounds like this guy lacks that ability. I've spoken to other people who bullied kids back in school and they felt really bad about their behavior, which is a normal and healthy reaction once you mature. So either he didn't mature, or he lacks empathy. Or both. And I need to tell you, that you might never get an apology or any remorse from him. The important thing is to work through what he did and recover from the trauma.
I was molested when I was a small child. And sexually abused by my first bf at age 16. Plus was abused as a child. I no longer feel anger toward the child molester or my ex. When I use to see my ex at the mall, I would literally almost collapse on the spot and faint. Luckily I could duck into stores to avoid him, but a few times I barely made it to the bench because I couldn't walk anymore. So I definitely get where you're coming from.
I just want you to know, that you might never get that apology or empathy, so you might have to make peace without either one. You were probably just an easy, available target and there wasn't any other motivation. But that's mere speculation on my part. I couldn't tell you for sure.
Just know that you are not alone.