I lost a very dear friend with FFXI, and the same thing is happening with another person I care for, so I just guessed you may have experienced the same thing.
It doesn't really look serious if you're not in it, but mmorpg CAN become like a drug. And the choice to end playing is completly up to the player, since it doesn't have an end...
I'm really, really sorry you had to experience this, because it's painful. And I'm sorry your friends also got addicted with other games. It's always bad when you lose someone, but when it's over some games... geez, it's absurd.
I hope you're other friends will be by your side