I think romantic_thi3f is pretty on the money, and I totally agree that you definitely deserve your place on these forums, or in a professional help setting, or wherever. Sometimes when we feel a bit excluded we forget that we have a rightful place in this world, and it's totally fair to take it!
Before I theorise, I want to say that feeling excluded at school is SUPER common and SUPER shit. It's a time where everyone is trying to figure out who they are and who they want to be, and they're trying out new behaviours (like exlcuding others), which aren't really "them", but they may be just trying it out to see how it feels. I know that since I've grown up a bit, I've got in touch with others from school and apologised for things that at the time didn't seem that harmful, but now when I look back, may have been a bit alienating or insensitive.
The great news is, in my opinion, that as you get out of school and into a world where you get to make your own decisions, life just gets way better for stuff like this. You choose your own friends, or meet people through work, or through uni, or a hobby, or just at the pub! But no one forces you to hang out with anyone else, because you're not in classes or anything, so you can make your own world. That may seem daunting if you feel you don't have strong friends, but honestly, I just feel it gets easier and easier as you grow up and learn to be happy with who you are.
It would probably be helpful to talk to someone like a psychologist, if possible, because sometimes when we get ourselves into a strong mindset, for example, "I feel I'm unwanted by my friends", we can get stuck in that headspace, and start believing that over all else, even evidence that says that you ARE wanted.
I always had a few friends at school, but I didn't know real connection until I met my absolute best friend, my (now) wife, and once you make a connection with someone so strong, you realise that the rest is just waiting. All you can do to prepare is to learn to be ok with who you are, and that you're not going fit in with everybody (and rightly so!) School is just a super tough time because you get bunched in with others and everyone is expected to find their buddy. Your best friends/partners/buddies/mates are all out there, they're just waiting for you to turn up.
Hang in there, and definitely reply if you feel like it, you absolutely deserve this space :)