I can’t cope with my existence or the duration of my existence

The fact that I’m alive gives me a strong sense of impending doom, like I only exist cause my mom baby trapped my dad. I genuinely don’t want to be on this earth and i haven’t for a long time. The fact that I could live to be an old lady is the weirdest thing to me bc I was never supposed to be here in the first place. I hate who I’ve become and I hate that I’m not someone who is a better person. But that saying that’s like “as long as you’re alive you can restart” it’s so wrong. Because I’m young yes I’m 18 but I can’t change the past and I cannot ignore it either so I can’t restart. And I hate that. Some days the only way I think I could restart is death. But I don’t know what’s worth it anymore so I’m still here.