Well in my case it's not as severe as voices in my head telling me I'm useless, I just know I'm useless. My hatred for myself ends up being an implicit one where I don't actively hate myself but it's something I can notice. Due to this I just cannot comprehend the advice which goes just love yourself. Like even if I do end up following stuff it feels like I'm faking it leading to nothing.
Funniest part is I thought this would just go away once I felt a connection to people and my existence actually mattered to them. Funnily enough I'm at a point where I care about them but not myself.
I also defended hating myself at one point cause it helped me be extra cautious if I thought of myself as the worst person in the room. This prevented me from hurting others. Boy did I learn later that my inaction also ended up hurting people.
Also when it comes to work, I can't do anything for myself because I don't care about things where I'm the only one affected.
I end up compulsively finishing work where others are affected tho.
Funniest part is I want to stop hating myself for myself. The irony.
Anyways I sort of think I have a reason for why I hate myself? Will put it in as a reply.