Changing Seasons

I have to lose 17 pounds before surgery (this is to remove the fat from around my organs). That's like telling me to lose 100 pounds before surgery. I have yo-yo'd up and down so many times in my life. I've heard that losing weight and gaining weight over and over can lead to diabetes. I sometimes think that that is what happened to me? Who knows genetics, food choices-everything seemed to not be in my favor. Anyway I have to lose weight before I have to have surgery to lose weight, I mean really doesn't that sound moronic to you?
Those psychological games that I play with myself goes like this:

You can lose the weight(Cheerleader in my head is cheering me on).
This attitude can last up to a full week-See below (I wrote this 2 days ago):
I have lost 5 pounds this week!! I'm excited and am trying to stay on track. Getting started is usually not the problem, it is staying on track that is my problem. I'm enjoying the healthier choices that I am making as far as food is concerned.Sugars are in check and I am feeling great. I'm hoping that the excercise will soon follow suit. I may be able to do this on my own!! I'm losing weight, I can do this (Seeing myself in my head-I may not even need the surgery?!?)
-----then------
Today:
What the heck was I thinking? I need help beyond my control.... I can't believe I let myself down again. I ate chocolate. I'm craving unhealthy food and have eaten some unhealthy food.
This attitude begins to invade my work (not as confident as I should be), my relationships (I may not return your phone calls) and my home life (I can't get up off of the sofa to bathe my son, fix dinner, do laundry, clean my house.)
The reality is that I need help because this cycle can happen once a week or even daily. I can't do this on my own.