I'm not sure if the information provided here will be enough to even consider a type, but I can try.
WARNING: really long thread. lots of history for background info's sake.

We first met during a math tutoring lesson. Back then, we were both in the danger of miserably failing the 8th grade because of mathematics, and that was the only thing we had in common. When I first saw her, I perceived her to be one of the most uninteresting and boring persons in existence. I was right, for the most part. Her weird (to say the least) mannerisms, slothful and spaced-out way of speaking and demeanor, combined with a not-so-radiant appearance attracted the mockery and teasing of every dickwad possible. She got made fun of a LOT (but this is middle and high school for you). We ended up landing in the same high school and group but haven't spoken to each other for a whole two years.

I don't really remember how we came to be friends then, I just remember we somehow were. It was a very short-lived friendship, though, one that ended with a #deep feelsy talk about people and relationships, her invalidating me, me feeling belittled and furious and calling her a hypocrite, and her blocking me on the messaging app that we used back then. And then there was silence.

For about a year and a half, we haven't spoken to each other at all once again. *She* was the one who first messaged me, asking for some schoolwork sheets (which I found odd-- Why would you unblock someone that you fell out with just because you need some schoolwork-related stuff from them when there are 16 other classmates you could ask? ).
Schoolwork turned into small talk, which turned into banter which turned into actual-talk, which turned into a friendship. I recommended Twin Peaks to her-- I was in love with the show and was halfway through with it back then. I got the impression that she'll love it as well. And she did! For the longest time, that show was the cohesion element between us and it did a great job greasing the wheels of our friendship. We started going out together and that's...when I didn't feel too well about things anymore. She seemed genuinely disinterested in everything I had to say, lmao. The burden of maintaining the conversations and having them not fall into awkward-silence territory fell on my shoulders entirely. Her favorite activity was complaining and whining about how fake people are, apparently. She was the kind of girl to post "I'm not like the other girls" photos on her Facebook, but that kind of died out over time...and I'm sooo glad it did.

She seems to be a weird mix of emotionally subdued and tone-unaware in conversations. The latter was specifically embarrassing to me a couple of times . She is SO LOUD sometimes. And she seems really unaware of her tone as well. We'd go on walks on summer mornings together and chit-chat, and her voice would echo through the streets. I'd awkwardly smile and look around for other people and their expressions, in case any of them hears us. We had a talk about BDSM in a public park and she just had to make sure that the whole alley knew about her stance on BDSM LOL. But otherwise, there is no emotional edge to her voice. The most she does is talk a bit squeaky-up-and-down when she's involved or complaining/outraged about a topic, but otherwise, it's really...dead.

At school, she's reclusive and quiet. You won't hear a single word out of her mouth for the whole day, sometimes. I'm loud, make shitty obscene jokes with some classmates. We both can't wait to get home and for the shitshow to end, though. Out of school, it's the other way around: She goes out, is really social, whereas I could stay inside all day.

I convinced her to change her life plans completely. She seemed to lack any direction in life when we first started talking and appeared content with the idea of going to the Netherlands to major in Business...even though she never had a penchant for that crap. Nor did she like it. But her parents did. "Jobs for the future" and all that. As cliche as "do what you love!" talks may be, it didn't seem that obvious to her. So I talked her into actually *doing* what she loves, and now she's working her way to be independent. Speaking of independence, she said this is one of her most sought for ideals when it comes to the future. Kinda peculiar to me, when I think of how she was so fine with the idea of throwing her fate into the arms of her parents so easily.

A thing that got on my nerves is that she's really childish :/
She wanted to spend 27.000 pounds as a loan to go to MET (the most expensive and prestigious film school in the UK, methinks). I told her how stupid of an idea that would be, considering she has no filmmaking experience whatsoever! And film, like every other art form, is something that you can do without standardized preparation as well. It's nice getting training, sure, but you can't really teach insight and creativity-- two elements which I think she seriously lacks, but I never had the heart to tell her honestly. She already perceives me as a pretentious, artsy boogeyman and I don't want to further that image. Gave her examples of directors, writers, photographers, musicians, all of them had no tangency with academia and managed to become figures we cherish and enjoy the works of, today. She ended up agreeing that her idea was really silly after all.

It's okay to vent, but please do specify if all you want is venting beforehand. I wound up writing a paragraph-long piece of advice for her once and her response was "I'm going to eat", turning a deaf ear to me completely. That pissed me off like no other thing in our friendship. If you find my advice not fitting for you, or even redundant, I'd rather have the person mention it to me, instead of not being receptive to my attempts to help them at all.
Our "friendship" has been going downhill more and more every day since we started talking again. I was/am aware of this, and for this fact, I've been distancing and not putting much faith in the friendship myself. I see her more as a buddy or acquaintance nowadays, not a friend. She's been using me as a personal editor and (un)professional official movie/book recommender.

As of today, writing this, it's her birthday. I suck at remembering dates; The only birthdays I know are mine, my father's and my grandma's (because it's on Halloween). She got really offensive this morning when I messaged her about a different subject and said: "You chose the wrong day to talk about X with me."
"Why?"
"What day is it today?"
It then hit me that it's her birthday. Saying "Happy birthday" then would be really silly and would ruin the mood. She'd know I forgot and wished her a happy birthday just because she said so. I got really defensive because her attitude bothered me; The day had literally just begun, it's 10 AM. It's as if I'm her husband and this is our Golden Wedding or something.

I'm 70% sure she sees me as a pretentious artsy snob and that she doesn't care too much about the advice I gave her, even though she maybe internally-recognizes that it helps/helped her, you won't ever see her thanking me or actually admitting my contribution.
I see her as childish, deadpan and naive (if such a combination is even possible).
I'm not sure how much of the "spaced out" impression is true and how much of it is actually just being...slow and slothful, once better knowing her.
I gained, over time, a wicked satisfaction in teasing her about her try-hard moral righteousness. She seems to always strive for it to the point where it seems fake and ridiculous to me.
A happy example of that would be when I was swooning over out art teacher once
She smiled and said "Stop it dude"
"It's not your business who I'm fawning over, pfffft"
"Yeah, it's not as if she's married! And has kids!"
"Affairs exist, y'know"
"They're immoral!"
"ThEy'Re ImMORal"
She then proceeded to smack me and I laughed. That was some good banter, but sometimes things are not as fun as I intend them to be between us. I get a kick out of calling her "Hypocrite" sometimes, as a nod to our fallout from two-three years ago.

If you find all of this type-worthy and made it thus far, congratulations!
Awaiting input. There miiight be more stuff worth mentioning but i'm sure i forgot it. Ask more questions and i may be able to get the answers straight from her.