I have a rule when it comes to eating. It's quite simple actually. I am allowed to eat only food that fits into the BFL program with my own twists of course. However, I am also allowed to eat any food that is offered to me.
The only exception I make is in the first two weeks of the program. I'm a believer, and have proven to myself, that the first two weeks are the most critical. If you can get through the first two weeks of any program, you're in the good. You will continue on regardless of any slip ups.
If you eat food that is not appropriate for your particular diet during the first two weeks, you have a high likelihood of failing and having to start over. However, if you eat naughty food later in the program, you'll be more likely to get back on the horse and keep going.
I think the problem with most failings is that people eat a bad meal, they have the craving for a cookie, and they eat it. Then they feel guilty, say skrew it, and then decide to eat whatever they want the rest of the day. This is fine later in the diet, yet it is not fine the first two weeks.
During the first two weeks you're more likely to say "skrew it" for that day, and then have trouble getting back on track the next day too.
I find that if I eat good and exercise, even on my free day I don't want to eat too bad. I don't want to skrew up a good thing. Eating right becomes a habit.
The dilemma comes in when someone brings food to you. My wife's aunt -- on the fourth day of the program nonetheless -- brought us a homemade meal of chicken, green beans mixed with bacon and butter, and mashed potatoes made with butter I'm sure, and two desserts and home made bisquits with home made honey.
Ahhhhh, my taste buds were salivating. And I ate all of it. Well, except for the dessert that is. It was easy to avoid the dessert because it was chocolate cake and I don't particularly care for chocolate to begin with. So I saved myself there.
Still, even when you are dietiing you still need to live your life. It's okay to eat a meal someone prepares for you. If you go to someone's house and they offer you a meal, take it. You only look rediculous when you turn down good food.
I wouldn't turn down a beer someone offered either. I'd even have two or three. Heck, I'd even get drunk if the opportunity presented itself. However, you must never forget the goals you set for yourself. It's okay to have a fun day now and again, yet you must get back on the horse the next day.
It's ideal to save your bad diet days for a free day. Yet life is life.