Fat girl, gone thin, got fat again!!! (Ex Ed, Insantity)

Hey all, I used to weigh 18.5 stone, lost 8 stone of that in 5.5 months from anorexia and bulimia about 8 years ago. I lived like that for a couple of years and then got 'well' from ED. I rebounded back into binge eating. Started starving again, lost the weight....started eating normally and was living at a comfortable curvy/slim weight for a few years. Moved city and went to Uni and at uni gained 2 stone (28lb) over the 3 year period. This was just through comfort eating, stress, and a lifestyle based on sitting in the library. Well now I've finished uni and I've gotten huge and I'm so unhappy with how I look and feel I'm my body. I've quit my job so I can just have a summer off as I'm starting a Master's in September. So today is the last day of work and as of tomorrow my time is entirely my own!!! I'm feeling the impetus to make real change to my diet and life as of today. I stepped on to the scale and I am a huge. So it's time to get it off. I don't want to be this size for my graduation pictures, I have to look at those for the rest of my life! So I now have a good couple of months to shift some of this flab. I could lose 10lb by then! I'm restarting Insanity tomorrow and going to make a concerted effort on high protein, low carb diet. I would really appreciate anyone's support. My partner is really supportive but is also like "there is nothing wrong with you" which isn't really very helpful, and also keeps asking me to go out for dinner! Arg lol. "No" is becoming my new word.