I really feel for you! I think I could have written your post. In fact, it wasn't that long ago when I reached 165 lbs. and that wasn't my goal, but it was getting there and then I just started to sabotage myself. I think there were many reasons for me and they are probably not the same for you, but I thought I'd just brainstorm with you a bit. First, I have migraines daily and that really gets me down. I struggle with a low grade depression and I use food to fill a void. Second, I remember the beginning of the end. I went to Las Vegas with my husband and I bought myself a size 10 adorable dress at BCBG (one of my favorite stores). I put it on and thought it looked really good. I saw my husband and he barely responded. I went out and sought some sort of looks and saw none. It was like I was still 220 lbs. So, what was all the effort for? So, part of it is my desire for attention stemming probably from being ignored a lot in the past, but that's a whole other story!
I've become somewhat addicted to comments from people when I lose weight. So, whenever I drop a lot of weight, everyone gives me tons of complements and attention. This is not good. I think the main thing, though, is that I'm a food addict.
So what can you do? Use me as an example of what not to do.
I am back to my plus sized clothing (size 16 or 18, depending on the brand) and right now, I could have been a size 8 or 10 at most. What helps me is to just have one good day. I tell myself that no matter how I'm feeling or what the excuse, I will have one good day.
Try to identify some of your triggers. For me, my biggest challenge is when I'm downstairs by the kitchen alone at night. I shovel mass quantities of food into my mouth regardless of how it tastes. So, the best thing for me is to go to my room and close the door by a certain time.
Have a tangible goal. That dress that I bought? I have hung it up in my room so that I can see it all the time. It's a reminder of what is possible. Yes, it's a shallow reminder, but who cares if it works?
I hope this wasn't too much about me....I just thought I'd post some of my thoughts in hopes that you won't do what I've done. Coming to 3fc is a huge inspiration.
Finally, I don't know how you've done it so far, but what has always helped me (when I do it) is tracking my calories on my iTouch. I have an application called LoseIt. I think you can keep one online and you don't need an iTouch. It's free and it's great once you get into it.
Best of luck. I hope you can figure this out soon.