I never thought I'd be writing my heart out here but here I am

I get super down about small things, it feels like my chest being crushed, unable to breathe or do anything. my parents divorced when I was 9 I think and i now live with my mum, my dads living in germany where he was born with his grandparents and is unemployed. I got bullied a ton as a kid, and was never really sided with by any adults in my life. My sister has a lotta problems like autism depression anxiety and stuff that causes a lot of attention to be put on her, which usually leaves me ignored. It was fine before but I think all the stress and shit piled up and arose when other stuff started happening. I've never really loved myself, or really liked myself, my now girlfriend would encourage me to love myself and it worked ill admit, but at some point pretty close to then I started hating myself again. My smile, my face, my features, my body, I hate them. Couldn't have helped that my dad used to always comment on my smile on pictures. So i have pretty much rock bottom self esteem which sparks my inability to feel cared about, craving but not seeking attention from those I'm close to, just hoping for someone to make me feel loveable. My friends are super nice and I make sure to stay away from anything that could hurt me, they just don't know how bad it really is for me. I have fun, I smile, I laugh, everything but I just feel... empty. Like I shouldn't have enjoyed myself, that no one else had fun or it was a waste of time. I can't take care of myself really, if I ever try, try to keep my room clean or clear up after myself, there's always more, always something 'simple' I can't do. I only really play video games and listen to music, I've tried to get into something else but I never end up commiting, I dont even think those things bring direct happiness, just the only thing that I can hold on to, it's exactly how I want it to be. I can't stand change or things not being how I expected, it kills off my mood. Looking at the pain of other people, feels like I can't really complain, but who am I to decide that, I can't even see myself scratching my skin off till it bleeds as even a little bad, it just helps me cope is all, no 'I deserve it' or anything, or maybe so, it's hard to understand my thoughts. I'm kind of just tired of trying, a I said, whatever I do, or improve there's always more, so it's just so tiring, why even try, right? Only reason I'm still here and (somewhat) kicking is because I fear how painful killing myself will be. I don't see that I'll hurt other people as a valid reason to be alive, barely feels like anyone cares, even if they did, people get over it. I struggle a ton in school, I'm smart for whatever reason, considering I never study or even really have enough in me to try, but it's just getting to do things, going there, doing homework, it's draining. I feel selfish for feeling all of these things, since people will always have it worse, my situation isn't even that bad, I'm just weak I guess. My friends and girlfriend try, I know they mean well but things like "you sure it's not just burnout" cut to my very core. They don't know how to help and I respect that, I just feel alone. I want to cut everyone off, let them be without me as a dead weight, but I can't bring myself to do it, I need them. It's just a lose lose situation isn't it, those who can help couldn't care less and those who want to help, cant, if I don't spend time with those who are close to me it just kills me off but if they try to spend time with me more often I don't want them to waste their time. Just, what the fuck do I do? I want to cry but I feel numb, I want to die but I'm scared, I want it to get better but I don't want things to change, why the fuck am I supposed to suffer like this just because I was funking born, nothings going to change, I've seen what people say, it gets better. As I've said, I'm not dumb, maybe it usually does, but for me it doesn't, stalemate I guess, I get to suffer because I exist