I can appreciate that. When your mates leave the game is even half what it used to be. The social aspect is a huge part of what makes it fun for the majority of players (i.e. not the hardcore grinders).
The guild splitting and friends leaving happened to me and I took a long break, but I'm back now. I occasionally play with my RL friend who appears twice a month or so, but most of the time I have a new guild who are all friendly and helpful, even though I don't know who any of them are in RL, and that keeps the game good for me.