Broken and hopeless,

I’ve been with the same guy for almost 5 years, he’s the most psychotic narssasistic person I have ever met. Im scared to leave him because I’m just close to his family, scared of him with another girl, we have good times occasionally and I just feel like if I leave I won’t find anyone else. I don’t think I’ll be good enough for anybody, Im not even good enough for him, so how can I possibly be good for anybody else?