Export to .idml and .inx should not be breaking any links. That said, the links still point to the ORIGINAL location, so if you send the files to someone else they will more than likley show as missing, or if they are conveniently located in the same directory as the document file they'll probably come up as modified.
It's breaking links no matter what I do, but I'm just going to also include a folder with all the links for them, that way it's easy for them to re-link. There doesn't seem to be a way around it that I can find, either in the program, or solutions online.
Are the links broken when you open the file on your machine? As I said, it's normal on some other system because ID links use absolute paths, but they should NOT be broken in any manner on the same system if they were OK when you exported.