You seem to have really been bitten by the "zero-width space problem." This is very unpleasant, I know. You might think that "show empty space" should take care of the problem, especially in an editor such as Sublime.
In any case, to detect the existence of these characters in Sublime 2, you can use this plugin. to display them.
As an aside, I spent several hours, if not days, on this problem several months ago when I was copying / pasting some code from a site that had one of the little nasty things.
I searched the Sublime 2 site for any posts related to this (e.g. feature requests, etc.) but didn’t find anything, so I don’t know if this is on their radar.
Note. The original version of this answer suggested that the zero-width mileage symbol was the same as the inextricable space, but it is not. Continuous spaces, while they still generate syntax errors, are much easier to detect since they “take up space” on your display (ie, “Look like a space”). There is also an “unoccupied zero-width space,” which is still different. Although it is easy to enter non-breaking space on a Mac (i.e. Option-Space), I don't know how to enter any space with zero width.