Interesting thread, thank Byteblock for starting it!
I've also been a fan of games all my life along. Especially solo, pretending to be the other players - and occasionally getting disappinted at the wrong copy of myself. Of course, with computers it became easy, having AI-controlled opponents.
Together with reading and daydreaming, gaming has always been a way to get some relief and pleasure. It's an alternative reality, where I somewhat am more alive than in what you might call the real world. Negative feelings appear but are easier to manage. It is rare, for instance, that a pack of nasty aliens jump out from your computer and taunt you all together.
What about changing interests, it could be subjective. Since I was a kid, I used to be obsessed with a game (such as chess or cards or board games) in a certain time frame, then drop it with no apparent reason. Some time later, I returned there, and did it again. No matter of special events, it was like I was "done". It's a trait of me, and didn't wear off with the time.