zeffyr: To me it sounds like genre fatigue. You're probably a strategy/RPG genre gamer, majority of your games spin around similiar basics. Maybe try playing a genre of games you have never or rarely played before? Driving, adventure, puzzle/logical, flight/train simulator, etc. Something completely new, maybe something you tried only once many years ago. It may 'click' again :-)
this helped me out of some gaming funks, im a huge fan of adventure games and most of my game time was spent with them, then i hit a 'funk' and tried out of the blue a shooter and had a blast. Then I tried strategy ... my nemisis and also enjoyed it tremendously. My next go to game will be a builder type game like Sim City, which I avoid due to the steep learning curves but I figure.. what the hay. Last but not least I may even go for a platformer, which I detest but who knows.. may fit the bill. I also started staggering games, play a bit of one genre, then try another. If a game didnt appeal, I stopped it and moved on.
all those tactics work with regular game funks, but game funks brought on by depression are another battle altogether, add in avoidance of pain with having to deal with disabilities and ergonomics of pc gaming, all of which can make it seem not worth it to crank open a new game. appropriate meds, counseling or having a good pal to talk to can help. try and getr some exercise to boost natural mood lifters... you know the drill
one thing to remember is that all phases of life have cycles, the bad times end and good times will come and vice versa. the trick is to make it thru the really bad time and not get beat by it. hang in there