Hi @Lonelyboy17,
I'm so sorry you've been treated so badly by her this year! Nobody deserves to be treated horribly. I'm just wondering, when she tried to talk to you and waved, did it seem at all genuine? I guess since she laughed after your response, it might mean it wasn't but I am curious about it. I agree that maybe you should try and talk it out with her as hard as it may be. If you do choose to do that, you can update us and we're here to give advice and support! Maybe if you do, it might clear up why she's been treating you badly, and it might also clear up why she decided she might try and talk to you again after a months time. Maybe there is some chance that she wanted to make things right (hopefully!!!) but I guess that is something that you might have to figure out. I really hope you aren't getting treated badly by others!
Like @Bre-RO said, if you haven't already, perhaps letting someone know like a teacher or trusted adult might be a better move too.