Starting over : motivation need (please read)

If you were to ask me 4 years ago to tell you a story about motivation I would have been happy to share it but these days my story is less about motivation and more about the struggles and difficulties about starting over.
My first journey on MFP was an amazing one. My son had just turned two and I had hit a turning point in my life where I was tired of being overweight. Being heavy was never something new for me, I had a lot of trauma in my young life with abuse and emotional abandonment and food, starting very early on, became my friend. I use to hide in my room when I was 11 and eat whole packages of cream cheese and boxes of powdered hot chocolate mix because I was searching for that comfort that I never had. Being fat became my wall, no one could hurt me because I was hurting myself. The worst part is 15 years later I still had that mentality.
March 2011 I made a change. I went to my first Zumba class and even though I felt as if I was going to die it was a pain that I learned to love. I taught myself to respect food
and treat it not as a comfort but as a necessity. I was consuming 1500 calories a day and exercising four days a week. I remember stepping on the scale and after three weeks I was down 13lbs. I was hooked, I was never going back. If you were to tell me back then that the hardest part wasn't losing the weight but keeping it off , I would have slapped you. In a span of 7 months I had dropped 65-70lbs (I estimate because I did not step on a scale for the first two months out of sheer fear). I remember going shopping and buying a sweater that was four sizes smaller than I use to wear and that motivated me to share my story on MFP with progress pics. The love and support was overwhelming and I thought "I'm never going back".
A few months after that post I found out that I was pregnant again and of course the fear of weight gain kicked in but I thought to myself "I have the tools and the knowledge this time so I'll be fine" jump to my two month checkup. My doctor asked me what I was eating, and I told her. At this point my diet/exercise had not changed. She told me that my baby was not receiving nutrition because I was technically starving myself, and that I was at risk for a miscarriage. Scared, I made small changes to my diet and four weeks later not much had changed, I got a serious talk from my doctor that if I didn't start consuming more calories that my child's health would be in serious risk. To be blunt, that scared the *kitten* out of me. I threw everything I knew out the window and stopped dieting and working out (looking back now I see how dumb that was). Six months later I gave birth to the most beautiful healthy baby girl so I can't say I regret anything but now I'm paying the consequences. I tried getting back to where I was but I was just to tired all the time, so I pretty much gave up.
Here I am today, and my daughter is 2 1/2. Three weeks ago I stepped on a scale and I was ten pounds less than my starting weight the first time. That was a serious kick in the face. How did I let myself get back there? So I deleted all of the progress on MFP and started over, fresh. I'm back to the 1500cal diet and I've been working out at home 4-6 days a week. I downloaded all my old Zumba songs and dance like a fool in my living room and I just started the Jillian shred. I've lost 9lbs in three weeks and I wish I could feel good about that but I find myself crying every night in bed because I'm here again, I'm at the place I swore I would never be again.
I wish I could tell you I'm a lion, a champion, a determined mother f'er, but to be honest I'm mostly sad.
Even though I will never look back I can't help but to dread the road ahead of me. If you're starting over too I could really use some love and encouragement to know I'm not alone, and that I shouldn't be ashamed to fall off and start again.