I think I'm only able to allow myself cheats on specific 'days'; birthday, Christmas, a holiday, a trip out. It would have to be different to normal days otherwise I think my body would expect it. For instance, I went off low-carb for four days at a festival, got back, and went right back to LC with no issues. But, if I was to sit here in my living room now and decide to have a cheat day, every day I was sat in my living room would feel okay to cheat :S