Welcome, j0ndysse! Your story sounds identical to mine... The last time I remember being thin was 2006. I've also avoided having my pic taken and don't have any full length mirrors. And when I dream at night, I don't dream of this body. I still have my 2006 body. It's not something I dream about having again; in my mind, that's how I look. When I look at myself in reflections, I don't see the fat. It's only when my pic is taken that I do, hence why I avoid it. I've been able to crash diet in the past and drop enormous amounts of weight, but as soon as I reached goal, or close enough to it, I'd go right back to what made me happy: food. I'd gain it all back just as fast, then add on another 15-20lbs. I finally decided in October that I had to make a lifestyle change, versus another diet. I had to do things I was willing to maintain for the long haul. I started off with baby steps; first it was giving up soda and juice. Then it was fast food. Then it was eating breakfast (I always skipped it then binged by lunch). I just started adding stuff out or in over time so that now it almost feels like second nature to have a piece of fruit for breakfast then hop on the treadmill after work. If you have to go slow, go slow.
This is the longest I've ever been motivated and on plan. I credit this forum for most of it, honestly. Just logging on here and checking in everyday gives me motivation to stay the course. It's when I start skipping days of checking in that I'm more inclined to skip days of eating right or working out. Another thing is that I don't think of the "big number" anymore. Before, I'd think of the total amount I needed to lose--45, 55, 76, 75lbs.. Right now I need to lose a total of almost 80lbs to reach my goal. But I don't think of that number. I think of 5. 5lbs. is my goal. When I reach that goal, I set another 5lb. goal. It's such a small attainable number, I don't feel daunted or discouraged to make it. I also joined a few of the challenges in the challenges threads. Having to check in daily or weigh in weekly helps to keep me accountable. I'd feel horrible having to post about a gain or to tell the girls here I've been lazy and pigging out. So I don't, which is great. So in only thinking of 5lb. chunks, regularly checking into this site, and making right food choices, I was able to drop 20lbs. so far.
Definitely post all you can and join challenges that you find interesting. There are so many helpful supportive people here. I hope this site works for you the way it has for me. Good luck and I look forward to seeing you around the forum!!