Monster Hunter Tri has been interfering with my writing, my work, my personal hygiene... okay, maybe not quite that extreme. There is a point, though, where games become something like obsession for me. I think it's always been that way.
As a kid, I grew up without a console in the house, and we didn't get our first PC until I was in high school. But I have a good memories of visting and playing Sonic the Hedgehog with my neighbours and sister. We did get obsessive about it, as was pretty much required to finish games then. I lacked experience, and so spent a lot of time watching rather than playing. But I remained very much involved.
We sat for many hours, engrossed and determined to progress in spite of the lack of save files. If you watched us you may have considered us zombies, with our eyes unhealthily glued to the screen.
We approached everything with that same level of persistence, though. On another week you might have found as equally engrossed in bike riding, or tree-climbing contests. It's easy to over-react if lacking broader context.
I have access to many games now, compared to about three games we had to choose from then. This might increase the risk of obsession, but really I find it's a rare game that really tempts me to those extremes. I know from experience these phases do pass, and balance is restored to life.