RuneScape's basically all I've played the past 11 years. Um, I hate it (especially now that nearly all of my old friends have quit), but I'm driven to keep playing it because "I've put this much time into it, I might as well finish these goals so I can quit" - repeated every damned year for the past 5 years. Basically, the sunk cost fallacy and the fear of missing out keeps me playing, though I have to imagine this is the same story for most MMO players.

I actually took a break in 2011-2012, which turned out to be the worst decision of my life. Life after the MMO is a fucking weird, scary place. My grades plummeted, I became much more depressed and anxious, and overall I had no idea what to do with myself during the 12-16 hours of the day that I would usually be playing the game. I had crafted my daily routine around the game, and when I ripped it out everything fell apart. So I've since started playing more again, though probably too much as of late. Even though I'm back to having "no life", it feels a lot better actually having some direction in life and being able to finish homework (and having high grades again) than to be lost, failing at everything, and contemplating my existence constantly.