Well, I'm maintaining right now, so I'm not so strict with myself. I have certain rules, though.
My SO knows enough that I only want to go to restaurants that have something resembling healthy food. LOL
For example, I will get the plainest grilled or broiled meat, fish or chicken that I can get. I will get a baked potato and usually eat the whole thing with a light slathering of sour cream and no butter. If there are steamed veggies, I will get those. But I don't forgo the potato. I love baked potatoes and the skin and I consider it a treat and I don't believe it's bad for me in moderation. I get salad dressing on the side and put very little on my salad. I use tons of hot pepper where it applies. I usually eat one piece of bread from the bread basket. I don't usually get dessert, but sometimes I get coffee. If SO gets dessert, I'll have a few bites. I prefer to prolong the dining experience anyway, and wait until I get home to have a lighter dessert. It's something more to look forward to and I enjoy it just as much. If we go to an Italian restaurant, I try to steer clear of the pasta dishes and get pizza if they have it. I like to get the margherita pizza (the "cleanest" option) and have them drown it in fresh basil. mmmmmmmmmmmmmmmmmmmmmm and only have 2 slices. It's enough and I eat it slowly w/a fork and knife. We usually go out to eat once a week. I haven't gained any weight and I enjoy myself. OK, getting hungry again....

Forgot to add that depending on the size of the meat/chicken/fish portion, sometimes I will let my SO "taste" a good 1/3 of the piece. And I never get alcohol. I usually get a diet soda and a water.