(Several people probably said the same, but I still wanted to reply)
I don't think you not getting a Staff rank is the problem, but you wanting it so bad. (Which I don't really get for some reason.) I guess everybody could say they want to be Helper so they can help people and make Cube a fun place.
You said Helper was your dream job (or how you'd like to call it), as if the only thing you want is the rank. If I were the one to accept proper Helpers, I'd accept those who wouldn't really care about the rank, but the ones who thinks they could make Cube proud.
You kinda sound like someone who just lost everything and needs to be helped with a rank, you shouldn't be beating yourself like that. Does you not having a rank mean the end of the world? Do you have to leave your friends because of this? To be honest, I thought that that's the reason you were here, because of the awesome people around here. Now it just seems like the only reason you came here was to become Staff.
I feel like everything we had (stuff like fun and random posts) was litterly nothing and I do feel a little betrayed and used. It probably sounds way to dramatic, but that's how it is. I still think you are more than that, though.
If you think you'd be a good Staff member, then you wouldn't stop trying and aiming at it. Don't give up because you're not a Helper (yet), keep on going because you have a chance. And doesn't helping people around and making fun here already feel like an achievement? Tell me, is it really about having permissions and a Staff tag?