Well when I was a WOW addict, all I played was WOW. I periodically still bought games, but I never played much of them. I felt guilty two-times over. First for buying games I barely played and secondly, when I would play them, I'd say to myself "I could be leveling". Finally, I woke up one day and never logged into WOW again. It wasn't a conscious decision, it just happened that way. When I realized that a month or more had passed WOW-free, I began to explore new games as well as many of the ones I shelved during my WOW obsession.
Now, years have passed since then and I still have a hard time finishing games, but it's not because I am consumed by any one game. It's just there's only so much time in the day to do all the things I want to or have to. I have to be choosey with my entertainment time. Additionally, I almost never buy any title until it drops into the $40 price range. I am more concerned with getting my money's worth from a game rather than finishing it. If I can experience even just a third of a game but still have a great time during those hours of play, I am happy. It's the journey that matters most.