I think that one of the keys to keeping both your WoW life and your real life balanced is by identifying your priority list. Every once in a while do a reality check and make sure you're keeping it in line. For me WoW sits somewhere between work and sleep (then again, I've never slept much). My guildies know that I will not be on on Friday nights, that's "sister time." I do play WoW when I'm on work trips, but I never go anywhere particularly exciting.