That IS a whole long awful story. A LONG AWFUL story. So I second the above. Why would you expect such a LONG AWFUL sequence to be resolved in less than a year?
Going back to exercise at this point, in my opinion, is playing with fire. If you need something to ‘work’ at, then work at changing your mind just as hard as you’ve worked at changing your body in the past. Work at changing your mind so that you accept and actually like (love?) yourself no matter what size your body is. It is only when you unconditionally love your body and feel a true physical desire to move that you should go back to exercise. Your eating disorder will cause a desire to move, but that desire comes from a sick place-it is driven by a need to alleviate the anxieties about your body being ‘too big.’ In my opinion complete rest is necessary until you can fully accept yourself at whatever size. If you go to the gym now, you are doing it to try to change your body once again. You will get sucked right back into the rabbit hole. Your issue is not your body or the size of your body, though it may feel that way. Your issue is the way your mind has adapted to view food, weight, and exercise.
Ask yourself this question: If you knew that working out, lifting weights, or doing other formal exercise would absolutely NOT change your weight or the way your body looked, would you still want to do it? If the answer is no I don’t think you’re ready to hit the gym again.