It is a game, she is a person. If he can't or won't make that distinction, there's really not a lot left to do: if you really think it's sucking his soul, you should treat it with the same gravity. Otherwise, encourage her to get out of the dead-end relationship and find someone who sees her for what she is.

I read something recently about the reason behind the WoW phenomenom could be related to depression, and the inability of the addicted to form normal relationships through more traditional means. I think there is some truth in that, but also think that addictive-personalities are vulnerable to being sucked in. I suppose the best thing to tell her is treat the guy the same way she would if he got hooked on a drug. If she wants to continue the relationship because she sees his value, then she needs to go through the same steps as if she wanted him to kick smoking crack. However, if she doesn't think there is anything there, then she should walk away, nice guy or not. My boyfriend has been really receptive to comprimising, and I went into the "negotations" thinking he would never give an inch. I followed all of my friend's advice and didn't tell him I hated the game (he is well aware), nor did I say he could not play any longer while at my place, I instead asked if there were days he absolutely had to play, and asked him if he would have "us" time on other days. Because he was willing to do that I see he does care that we have a healthy and successful relationship. And for the nights he plays I try to go out with friends, because sitting around hoping he'll pay attention to me is maddening. Besides, alone time is as necessary as us time.

Ive said this before, I should just make a copy / paste of this :

He has to WANT to change.

If he gets to the point where he is depressed, or temporarily sick of WoW, or expresses a desire to quit, then she has a chance to swoop in and replace WoW with something else.

Eventually he WILL get sick of WoW. Its up to her to capitalize on it. However, it can literally take YEARS! If it looks like its going to be awhile, she may need to write him off, let the next woman fix him.