Being ghosted by a friend

Hi when I was 13 me and my best friend at the time got into a really big argument. Things got heated, I eventually tried to apologise and sort things out but she ran into the bathroom stall and refused to hear anything I had to say.

She ignored me, then never spoke to me again at all. And just aired me, so eventually I just did the same and we became strangers.

I thought I got over it I am now 19. And it’s hit me like a brick wall the emotions. I am heartbroken, so sad she was my childhood bestfriend, i dream about her sometimes and tear up when I think about her. I stalk her social media’s from burner accounts, she is a completely different person we really are strangers now.

I just don’t know how to move on, it’s so hard. Looking back I realise it was just a stupid fight that could have been easily resolved. Why did she ghost me, how can I move on.

I have to much pride to go up to her and speak to her if I see her because I’m scared of being rejected that would break me