I need to take the GRE soon and need some direction. You might want to take one of those Kaplan-like courses. If facility with mathematics passed between people like osmosis, we'd have a solution to the problem in mathematics education in this country. I think there is way too much emphasis placed on a very tenuous and ill-supported theory of brain function. Insisting on this almost inviolate distinction is often a way of avoiding mathematics, and sometimes literature.
Most endeavors require a full brain.
I'm not certain that mathematics is so unpopular. The problem is that people have a very narrow conception of what mathematics is, believing it to be computation, glorified bookkeeping. Once exposed to real mathematical ideas, they generally respond. Likewise, if all they were exposed to in English class was sentence diagramming and punctuation, they wouldn't have much appreciation for literature. I also particularly enjoyed my first course in mathematical logic because of the way it resonated with so many of my other interests.