First off are you sure this isn't just a troll? I think it is.
That said, I have read all 4 pages of replies, and i cant see many mature or helpful responses. So here's my 2 cents, hope its not too long.
What i don't get is why you need to dump the poor girl because she isn't spontaneously amazing at something you've been doing for 5 years. Maybe think about why you are even considering that. 6months isn't a long time at all for a relationship, but its one of the "make or break" points of a fledgling romance, if after 6 months your finding cause to end it whats gonna happen in a year? or even after 2 or 3? The way i see it is if someone has major flaws visible early on then jump ship and find someone better suited to you, rather than wasting years on a b*tch who will ditch you in the end anyway.
Now if you do want to stay with her here's a few tips:
Do you have to play wow together? Since vanilla Ive known a lot of guys try to get their girlfriends into wow, its cute and all, but rarely works. Its something id never do, i like my hobby of gaming, its mine, i would share it with a partner whos already interested, but im not gonna drag a girl into that if its not her style.
Time apart is vital in a relationship, living in each others pockets just makes you subconsciously resent the other person because you don't have any sense of self anymore. Also its important not to change drastically for another person, if you have to change that much for someone then they aren't the person for you. So never ever quit a hobby of yours for another, it should be your choice, for you, not for them.
Now if she really does want to play wow, why not let her do that, alone. She will learn far more working her way up from lvl 1 like we all did first time round, than following you through instances/BGs. Let her find the game for herself, dont spoon feed it too her, let her see if she actually enjoys playing, rather than playing with you. Then when shes got the hang of it pop out the char that youve been secretly leveling to keep pace with hers and go: "hey baby, want me to tank that boss for you" (smooth).
Im guessing your raf-ing, something i wouldnt do with a person new to wow, its just too quick, you cant get a full understanding of a class on the 4day burn up to lvl 60. Get her off the rocket mount and into slow leveling 1-60, its as true in wow as in all things - you have to crawl before you can walk.
If thats TLDR:
Are you breaking up with her for this or something bigger?
Time apart is good, she doesn't have to do what you do just because you do it.
If she wants to do it, let her do it herself, so its hers not "yours".
Never give something you like up for a person, you shouldn't have to sacrifice to be with the right girl for you.