I would definitly stay. I don't really care if they're in the game or not - if they're my friends, then we have already another way of contacting each other so no nostalgia, and I'm the versatile type in a MMORPG. I'm always ready for a chat, like meeting random people but never seek for a deeper relationship. The friendship I found were surprises more than everything else, and my first reflex were to detach them from the game.