“what motivated you to stay even though you hate every minute of it and noone in your school understands how much you hate every second and you just want to get out of there right this second and you come home crying every day and you just CAN’T STAND ANOTHER SECOND IN THAT **** place?”
I don’t know if this is very helpful, but in my case, even though everything you’re saying was true for me and probably most of my classmates, dropping out wasn’t an option anyone considered back then. So as hard as it was to go to school, and as much as we hated it, we didn’t feel like we had a choice. Which may have made it easier in a way.
Maybe you can try to tell yourself that you don’t have a choice. I would think that would make it easier. It sounds like maybe part of the hardship is that you feel like dropping out is an option, so therefore it’s hard not to.
Alternatively, can you switch high schools? Would that help or would it not make a difference?