My girlfriend doesnt really mind, as long as I give her what she needs before I start playing, she's good. Sometimes in the middle of me playing she'll just come up and grab me or kiss me or something, which basically means after this game, you need to do your boyfriendly duties.
I try not to play for more than 2.5-3 hours though, then she gets antsy/bored.
I live with my girlfriend, but she enjoys games as well so normally it is ok. She is horrible at Halo and my stats suffer for it, because she loves to try to play online. She says the game is pretty. In my head horrible stats are worth having a gf that at least tries to play.