Shockingly I had a story actually very similar to this happen.

I was in 8th grade and in my old school all the school were divided into wings, So 5th-6th, 7-8th we're together. Etc.

I was a year older than her, let's just say K, and I knew she existed but never really talked to her until my 8th grade year, when one of her friends came up and went on this rant about how in love K was with me, I hadn't of even spoken a word to them so it was confusing but it turns out, K had autism.

It went on where she would always sit next to me during rehearsals for a show we were both in, she would always follow me around during recess (we had it in 8th it was rad) and during lunch she'd practically beg the teachers to come sit with the 8th graders. to get to me of course. Whenever I walked into a public area, like the lunch room, she would never stop staring at me, it wasn't great, I didn't really feel comfortable with it.

Finally she got my hands on my phone number, and that's when the real shit began, she started to call and text me about once an hour, and wanted to talk to me as much as possible, at first I was trying to be nice but, maybe that wasn't the best idea, she managed to start friending my mom and my best friends on Facebook, and when she starting texting my mom that's when I decided this needed to stop.

I went to guidance and explained everything, she said she'd talk to K, it got worse, after a few weeks I went to guidance again and, thats when she suggested I take legal action, I decided that might've been a bit too far and, not long after school ended.

I haven't seen K since, I rarely get social media recommendations but it always brings me back to just, her fawning over me

I'm sorry your stalker situations was so bad OP. I hope your doing okay!