So I guess it's just that time

Every now and again I get these feelings and I'm going to try and explain them to you cause it's not exactly the best time for me.
So here goes;
Every now and then I get these feelings, that I am a loner. I sit in classes or go places wherever I am and I feel like I am the only person that notices my existence. I feel when I look at all the people and notice their faces it's like I am behind one-way glass. Like no-one would ever give me a second glance. And if they do, it's more because they thought I was someone else. And it's not just in public, in school as well. I feel like everyone has their groups and I have been kind of let go. Like there has been some things happen recently with my friend groups and I kinda feel like I have been replaced. And I dunno what to do. I rely on my friends so much; I have arguments at home, my mum is depressed, my sister is arrogant, my dad doesn't pay attention as he lives halfway around the world/ And no-one seems to really get that, I know you all say you do, but sorry most of you just don't get it. Every year on father's day I cry cause I only see my dad for max 4 weeks a year, you don't get what that's like until you have experienced it, divorced parents, sure it's difficult but at least if your dad lives in the same country, it is just that bit easier. So then I turn to my school work, but you know it's always the same people above me, people I want to be able to coexist with at least but no, I feel like I am getting pushed back. I dunno. It's really difficult when you lose your best friend and your group to someone that supposedly "annoyed the shit out of them" before it all happened. I dunno, maybe I'm just not good enough, not into fashion or hot guys enough or just not like them. And I dunno, maybe it's just not me to be part of certain groups but sometimes I just feel like I'm not good enough for certain people, like I am not in the class range they are. But I don't see how they can judge me as being worse than them. I just don't get it. I try and see people that don't annoy me in the same light as I would my friends, but you know, everyone wants to be part of the crowd. I just never know who is the crowd or why there is a crowd or what even is a crowd. Sometimes it'd be nice to be able to talk to anyone but no, I am so socially awkward and I never know what to say. I dunno. But yeh, that's my emotions at the moment.