For the past month I've been bullying my ex-friend
No way. Why are you bullying your ex-friend?
For a long time he believed I'm a pathological liar and a scammer, now it's easier to beat him up without having his friends stopping me
It's best to let petty arguments stay in the past. You should not be bullying anyone at anytime.
I promise to stop it.
Thanks a lot, no one deserves to be bullied, especially someone who was once your friend. I hope you can apologize to them and attempt to make up with the, because they didn't deserve any of this. You can only try to make yourself a better person now.