I'm still not over my best friend ghosting me five years ago.
Why do you think they ghosted you?
I don't know if it was because I annoyed him too much or he was too busy with his own life.
I'm sorry to hear this happened to you. Ghosting someone is rude so it makes sense that you're upset. I would suggest trying to forget about him so that you can focus on other people.
I want to, but it's hard.
I understand it's difficult to let go of the feelings you have for someone, especially when they ghosted you and gave you no closure. It's in your best interest though to try to move on. If you instead focus on the positive relationships you have in your life, you will feel better and more fulfilled.