I understand about
your mom not wanting to believe/let you go to a therapist, my parents are the same way-- it took me more than five years to try and convince them to let me go once to therapy! But you can't let her hold you back. Someone on here once said that parents are sometimes in denial about
their kids problems because that's how they cope with knowing about
the problems but not knowing what to do about
them, and I think that is absolutely right. I would go to school help and see what can be done. Sometimes if a school advisor sends something home to your parents it gives them a little reality check and makes them realize that you really DO need to go see someone to help you through your thoughts.
It sounds to me, based on how long you've had this, that you have some long-term issues that you need to resolve. Something that happened in your past might have affected you more than you think.
Have courage and faith, and I know you'll be able to get through to your mom. Take the situation into your own hands, and keep thinking those things that you would miss if you did something to try and end your life or potientially ruin it. You can't do this alone, though. You've got to try and find help. Sending prayers and healing your way!