I am afraid to fail

I am always afraid, always afraid to fail. When I do something wrong at home, my parents always say: you are good for nothing, you are stupid etc..

I always feel so worthless... I also always think I might as well die, better live in heaven. But my parents are normally very sweet and they always say I am the prettiest girl. But at school they helped my very often with this fear of failing but it doesn't have any effect on me and I just driv myself crazy..

In class I always think about how much time the teachers spend.. they shouldn't... I am anyway worthless and a waste of time..

Plz tips on how I can feel better