S.W.
The only woman I know who successfully lost a lot of weight and kept it off never used the word "lose". That's a negative word and think about it, whenever we lose something we try to find it again! Instead, she talked about "gaining a healthy life". She took up ballroom dancing to be more active. This motivated her to continue to get stronger and healthier so she could dance more. She gained a liking for healthful, nutritious, food. She did this for a year. The transformation was amazing. But she needed to change her thought, words, and THEN her actions.
I met this woman in my Life Coaching class. The techniques I talk about are the ones coaches use with their clients. You can find life coaches that specialize in wellness, just google.
In your post, all your reasons for losing weight are negative. How about sitting down and writing as many positive reasons for gaining a healthy life as you can think of. Pin the list up where you see it every day. Pick one each morning and any time you fall into a negative, weight related thought, switch it out for the positive thought of the day. Changing our thoughts, words, and actions takes commitment and work, but it is the only way to make true behavioral change.