Everyone handles pain differently, me I deal with it. I broke my arm, and dealt with it, and twice broke my hand, it remains broken, and dealt with it... but I cannot take codine, I am allergic, and I have watched too many other people kill themselves with the other crap.
I do like the idea of a muscle relaxer, that is the first time I have heard of that one. A muscle relaxer is something that I may ask my Dr about, because I would much rather break bones, or have my teeth cut out than deal with the sharp stabbing chest pains everyday.
Good luck to you in which ever choice you make.
-Jason