Motivation and willpower

Any suggestions on how to stay motivated and stick to a "plan". I am almost 6 years out from surgery and am happier than I've ever been, but I have never gotten to the weight I had hoped for. I need surgery to remove the excess skin (40 lbs plus), just isn't an option in my life right now. I am a stress eater and I have two boys, both just diagnosed with ADHD (one is 15 and the other is 4) and I have my 38 year old brother living with me that has Stage IV throat cancer, on a feeding tube and can't speak as his voice box was removed in March....so to say I have a little stress is a understatement. I find I back in the world of prescription drugs to keep my sanity... but food is an obsessive thought for me......any help and suggestions would GREATLY be appreciated. I joined weigh****chers this past weekend and am hoping for a bit of success there...