I agree, it's rough to stop. I usually do well at stopping if I feel really full, BUT....if we eat out, ****, I'm paying for this food and I'm gonna eat it! Even after I get full. So when we eat out I do try to get things that would be acceptable as leftovers as well. That really helps.
But the worst part is even if I feel full, sometimes the food just TASTES so darn good....I don't want to stop! Probably because if something tastes that good, that means I'm probably NOT going to get that food again for a very long time. It means it was likely some sort of treat, and I don't want to waste it. Or if it's like cookies in the cupboard, even if I don't feel my stomach is hungry, I still won't be able to stop thinking about those wretched cookies until they're gone. Thus, no cookies kept in the house because I'd like eat a whole package of oreos in one day.
I really want a "normal" relationship with food as well. Have you ever heard of "intuitive eating"? You should read this post at a blog I've found recently. She's got some good stuff on there. And read the comments because she posts a lot of links on there in response to some of the comments, including my own. I hope it helps!

Thanks, Rapunzel, for that link. I found that very interesting!

I know that my craving to eat is MUCH worse if I'm bored, frustrated or feel deprived somehow. I eat to feel interested in something, to feel pleasure in something, when I am having a particularly slow or monotonous work day. On the days I'm busy, I don't think about eating when I'm not hungry.

I have the same problem and I'm trying to figure out WHY? I don't know if it's because I'm bored or if it's just because I know that food is there and I should eat it. I have come to the conclusion that I cannot have snacks in the house or in my office because I will eat it. I have to add more veggies to my diet and drink more water. I have to stop buy cookies and crackers. I can eat an entire box of cookies and crackers at one time.

Wow, I loved all these posts and I do mean "all". They so hit home with me. The wanting to eat all the time is so true and it does scare me. And just eating way, way too much most of the time. Gosh, so agree with all these posts. Thank you all for sharing.