My girlfriend is entirely happy with my level of gaming which is, frankly, rather low anyway. My base level tends to be about a two hour session two or three times a week, so I'm not exactly spending much on it anyway.
When new releases are on the table I tend to have a deal. With enough pre-warning and comparative payback I am free to disappear for a day or three (as happened with Resident Evil 5). Fortunately the number of new releases I am actively excited about is always quite small, the only things on the horizon for me are Left 4 Dead 2 (still don't know why its not called Left 2 Die) and Modern Warfare 2 (Call of Duty 6: Modern Warfare 2?).
However, under different circumstances I would agree to reduce my rate to about where it is now. I am currently not living with my girlfriend but as and when we've agreed not to be pissy about things we each want to do in our evenings.