About not knowing where she lives how about this approach, "I need to let you know that I'm changing my emergency contact info at work. Since I don't know where you live now, in case I'm injured or worse, they will now be notifying my (dad, mom, brother). So, you'll hear from them if something happens to me."
She'll either say "OK" (which is the likely response), or she'll give you her address.
Me 36 Husband 35 D5 S2 separated: 10/29/07-present Served divorce papers 1/22/09 "When the world gives out beneath your feet, it is time to learn how to fly."