Disclaimer: This is just my opinion of how this works.
I think this is one of those cases where the ones who need magic the most are in no condition to cast it. From what I've figured, magic is everywhere, although it's more at-effect than at-cause.
Basically, when these individuals bullied you, parts of your soul fractured off from you in the trauma, and starving and cutting yourself are symptoms of that. In order to cast a spell that would have effect, you need those pieces back.
The stirring up of empathy and remorse is something that I've experimented with as well, but 1.) no achievement of the ultimate goal so I can't recommend it and 2.) that's a lot of planewalking that I wouldn't recommend 'cause it cray-cray in the otherworld...and it isn't a spell like "ingredients list, step 1, step 2, step 3". But if your fractures have formed this dark gunky aura stuff, then find a way to throw it at the bully. I don't know how they'll take it or if it'll stick, but you'll feel better.
Otherwise: Nidstang. You can run that word through a search engine and just modify it so it fits better with the goal of getting that bully out of your space. Sorry, as I said, I have had no success with manipulating worldview and emotions of other people, but I have had success with the Nidstang.
I'm sorry you're in this situation. Bullies are the worst!