High Maintenance as a Moral Category

We had our senior thesis presentations the other day and one of our seniors wrote on the moral responsibilities that stem from friendship relations.  She took an Aristotelian sort of approach and during the Q&A section, a colleague raised the issue of high maintenance friends and asked whether it was a character flaw.  Is "high maintenance" a moral category or at least does it have an ethical dimension?  There is a difference being immoral and annoying, where do we put being high maintenance?