I want to be her friend so bad..

Sorry if there’s any typo, I’m learning English.

So, let’s first talk about me, I’m.. Not very good at making friends, I kinda start to panic and shaking when I have to talk to many people in front of me. And sometimes I don’t talk, like, 0 words for hours while being with 2 o 3 persons around.
I’ve never tried talking to any stranger, to try to have a new friend, and I’m very selective too. I don’t want.. “generic” people. I want to meet and have friends that are really good people, and of my like.

So, last year at school (I was at my penultimate year) a girl got near and started to talk to me. It was very concercing and confusing for me, I actually had to ask if I knew her or something.
She started to talk to me in every break time. Until she asked for my Instagram. There I knew that she was just a total stranger and wanted to meet the guy who was always in front of her classroom.
We chatted for a few days, we started to know each other a bit more and then she asked if I wanted her number, and so on.
She was a really kind person, calm, interesting, pretty good vibes. I started to like her a lot (as a friend) and I wanted to talk more, since I barely talked with her in person when she was near. I think that she doesn’t even know how I look without my mask.
But, well, the year ended, we got vacations, we started to talk a lot less as days passed by. She said that she was going to have a change of school, and of course, I wasn’t really happy. I didn’t try to stop her, obviously, but I let her knew that it was kinda sad for me.
We stopped talking then, just because, nothing serious.

And then, this year I saw her again, at my final year of school.
I tried to talk to her, ask her how she was doing, why she didn’t leave the school, she replied, but only once.
Hours later, nothing. Days later, nothing. I started to feel really bad… I didn’t want to bother her but at the same time, I wanted to keep her as a friend, so I sent a message asking if something was happening, nothing.
Days later I sent her a longer text, asking if we could start talking again, but she blocked me. I.. Cried a lot that night.

And, here I am now.
Seeing her everytime at the bus to our way to school. Seeing her at our breaks, our stops, our ways to the bus stops.
I can’t stop thinking about her, I really wanted to be her friend, that was the only thing that could make my last year the best year of all. Yeah, only that.
I talked about this with a few friends, and I started writting a lot of notes for myself, sadness, hate, reasons, saying everything that goes in my head. While making all of those notes, I got to the conclussion that I don’t want to hate her for this. It’s.. Not my style, and I still want to be her friend.

11 days passed since she blocked me, everytime that I notice her being near, I try to avoid eye contact with her. But I don’t want that, she’s not a bad person, I don’t hate her at all. I just want to understand her, make amends and, if we can’t talk again like last year, then at least I would like to greet her everytime that we see each other, at least that..

Sorry, that was a really long text, but right now I really don’t know what to do, or what to think.
I’ll try to make eye contact in one of these days, maybe even smile at her, and try to greet her when I see her or something.
But it may be weird, if she’s really mad at me, or if I’m bothering her, I would look like a creep.
I didn’t tried to send another message through Instagram yet, like “Why did you do that?” since I think she will block me there too.

I don’t know what to do, and this thing is really starting to hit me really bad. I want to stop being a lonely person all the time.. All those previous years were horrible. I’m not a very social person, but unlike with others, I really didn’t want to dissappoint her when we met.

What should I do..?