First of all you're neither a failure or inadequate.
By the sounds of it the thing you need at work is a champion; someone on your side helping to fight your corner. It sucks that seemingly you don't have that. Having a leader/manager, even if not yours or the store manager, who understands you and fights for you would undoubtedly make things better.
And on the other hand, I get not wanting to move because there's also the uncertainty as to whether it would be better or just simply different. It's a sucky catch 22.
I don't really have an answer or an idea for how to make things better, but you know where I am if you need anything.