do frendship trios work?

this year i’ve met two girls in my class group and we 3 became almost best friends (i’m saying almost and i’ll soon tell you why).
they’re both extrovert but me, an introvert. To be honest, i always felt kinda weird about our trio relationship. The rest of the Class has always seen us like the three mosqueteers, the elite squad and all that. I’m the one in the group that lives farther from the school, they both live inside the city so it’s easier for them to hang out. I always enjoyed staying by myself, but going out and partying as well. The more the time goes the more our friendship and even the misunderstandings and stuff just become more frequent. On top of that, and i don’t care about anybody who coul’d say i’m playing the victim, i’ve always been “forced” to stay at the last desk of the line that was occupied by us + a dude who ended up being part of the group in some way. Now, this friendship sure gave me good memories, but also made me feel more lonely than i was before first meeting them. During the second half of the year them two became friend more than we all three did in the whole year. I felt left out even more, to the point that many times i preferred to “ignore” them and talk with nobody else because i was always upset and sick of being the last wheel. they hang out without asking me too because “you can never hang out” alright?? at least the effort to ask?? it’s called courtesy, and apparently not everyone has it. When one of our two friends wasn’t school, each other always came at me because apparently they had no other chances if not just desperately trying to make me feel included and not left out for once. [small note: i already tried to talk to them about this and a sort of fight also started, not so long ago. School ends, and so does our chance to meet each other every weekday. Yesterday was like the third time they hanged out during summer break without telling me, (not even the decency to ask on our imsg chat) and after seeing both sharing stories together i started up a fight. I don’t know what my head was telling me to do, but i just dumped all the shit they made me go thru for all of this time, and guess what? they still told me that they didn’t ask me out because i ignore them on purpose, that i was making up everything for clout and that the one of the group ignoring others was me. Why can’t yall talk individually for once? I’m not sure if i did the right thing, but i regret nothing. Now i’m just going to pretend that this toxic af friendship never happened. it was the worst thing to ever come in my whole 16 years of existence