Survivor since 2009
The two things I resisted the most, but that helped the most in the end were exercise and sleep medication. I set the following limits for myself. Two sleepless night in a row mean I would take Tylenol PM or Advil PM the third night. I felt as though I was continually trying to sleep without help, but not letting myself get so exhausted. I just hated that feeling in the morning when my eyes would open, but I was tired, tired, tired already. Eventually (2 years later) I sleep well almost every night without taking anything.
I set a goal of 5 hours of exercise each week. Some weeks it was 15 minutes at a time, and some week I didn't get 5 hours. A weekly goal let me miss a day without feeling like a failure, and it let me start over every Sunday. After about 3 weeks on that plan, I had more energy.
It had long term benefits too, I'm a three year survivor and I still aim for 5 hours per week of exercise. I dropped 15 pounds as well!