If you're really bad at math, b-school is going to be a struggle, as it is indeed quant-heavy. I would recommend taking a math class or two at a community college to #1) improve your math skills (it is hard to do this on your own if you're really bad at math) and #2) see how comfortable you really are with math. If it's a big struggle even after a college class, then you might want to rethink b-school. I don't want to be a downer, but give yourself an opportunity to improve your skills before you attempt b-school.