why don't my friends invite me to anything

I think I'm probably overreacting but whenever my friends make plans together I never seem to get invited. I'm friends with lots of different people too so it's not just one group of people it's people who don't even know each other. everyone seems to be going places or hanging out all the time but they never invite me. like on Friday one of my first friends at college who I've known for like nearly 2 years now had a birthday get together and invited all our mutual friends except for me. I didn't even know it was happening because none of them told me until I found out that there was no point waiting for my best friend to finish his classes because he was going too. this doesn't even happen just outside of college sometimes in college I'll have to sit on a table by myself in break because they don't want to make room for me on their table, and if I am there they don't let me join in with their conversation. another one of my friends is going out soon for her birthday and they keep talking about it when im there. she keeps talking about it as like a girls night out and all the girls we're friends with are invited except for me. I feel like even though I'm friends with them I'm not close enough with any of them to be invited. my best friend cancelled hanging out with me today because he has too much work to do even though he wasn't doing anything yesterday and went out on Friday and last weekend and the weekend before. I always think maybe I need better friends but there isn't actually anyone else because everyone has already been with their friends for early two years and I've just been here. everyone already has their person so they don't need me as well.

Yeah, They are ALL definitely excluding you on purpose. I think they like the chase how you just sit there even though they ignore u. Think of it as some sort of entertainment. Man you need some better friends, try online or some other people? Even though everyone has their own person already, some people still want new friends.
Side note: your friends are horrible people but have you done something that they may have not liked...?

I think I'm probably overreacting but whenever my friends make plans together I never seem to get invited. I'm friends with lots of different people too so it's not just one group of people it's people who don't even know each other. everyone seems to be going places or hanging out all the time but they never invite me. like on Friday one of my first friends at college who I've known for like nearly 2 years now had a birthday get together and invited all our mutual friends except for me. I didn't even know it was happening because none of them told me until I found out that there was no point waiting for my best friend to finish his classes because he was going too. this doesn't even happen just outside of college sometimes in college I'll have to sit on a table by myself in break because they don't want to make room for me on their table, and if I am there they don't let me join in with their conversation. another one of my friends is going out soon for her birthday and they keep talking about it when im there. she keeps talking about it as like a girls night out and all the girls we're friends with are invited except for me. I feel like even though I'm friends with them I'm not close enough with any of them to be invited. my best friend cancelled hanging out with me today because he has too much work to do even though he wasn't doing anything yesterday and went out on Friday and last weekend and the weekend before. I always think maybe I need better friends but there isn't actually anyone else because everyone has already been with their friends for early two years and I've just been here. everyone already has their person so they don't need me as well.