I've never really grown out of it, but I did start playing a lot less around early 2005. Metroid Prime 2: Echoes had come out and I had finished it during the holidays, and then I started to get real serious with school so I basically stopped playing games for a while and reading up about them.
Around May that year I decided to start playing again and picked up a little game called Resident Evil 4. Was blown away, completely refueled my interest in games and it hasn't dropped since.