Deleting contacts in Windows Live Mail Directory

I regularly delete (or try to delete) email addresses from my hard drive directory, but they always show back up after an unknown period of time.  Some of the addresses I have deleted are for people who have died, including two relatives, who died more than two years ago.  Regardless of how many times I delete them (some as many as a dozen times), they will eventually show back up in my email directory.  Does anyone have suggestion(s) on how to permanently delete email addresses?  Thx.