That's most of players' problem. Their loyalty to "friends" they met online. Not realizing that you can make NEW friends somewhere else. How else did you get into your guild or previous guilds?
I, personally, dont view anyone online as a friend. They're acquaintances. Friends know everything about you, someone you go to bars with, someone who got your back, knows your family, knows your deepest darkest secret. Acquaintances, know enough to trust you and thats all. They will never have your back nor do they care enough about you. Yes, you have a common interest, in this case, raiding on WoW, but thats as far as it goes. They are just a voice over a chat program.
If this doesnt apply to you then just disregard everything i said. But if it does, remember you pay to play the game how you want. Not to please people you'll never meet or even hang out with. Also, when you were a noob, like everyone was at one point, you made obviously got into a guild and made friends there, without knowing anyone, right? Why cant you do it again?
Thats my story and i'm sticking to it!