Hello Shush,
I can totally understand how you are feeling. Yo yo dieting is such a pain in the butt. I have dieted on and off since I was 18. I started dieting when I was just 12 stone, and after 19 years of yo yo dieting I am not 23 and a half stone

My problem being that I would diet, then lose weight, then say stuff the diet, gain the weight loss back and gain more weight besides that.
My major weight gain was when I was first married and had a baby. I had the baby weight, and then we found out the baby was deaf, and I did a LOT of comfort eating. My husband started being the creep that I never knew he was, so more comfort eating. Then the divorce, more comfort eating. Then really bad health leading to three major surgeries for me. More comfort eating AND no exercise. I weigh more now than I ever have and it's my body that is making me stick to this latest diet.
I got MRSA after my surgeries, and I have wounds that won't heal any time soon, and although they are nasty, it's my weight that is the most debilitating thing. My ankles and legs hurt, my back gives me a lot of grief, I can't do the simplest of jobs without ending up in pain or out of breath. If I don't diet now I know I am going to end up disabled. A disability through ill health is one thing, but through my gluttony it's another, and it's time I did something about it. So I find myself here.
My tip to you is to perhaps write lists of what you can't do at the weight you are now, and what you will be able to do when that weight comes off. If you have physical pain because of your size, then keep that foremost on your mind. And the one thing I have to learn to do, and you as well if you are a comfort eater, is to learn that it's false comfort. It lasts while you eat, but when the guilt sets in and the scales rise, there is no comfort at all.
Good luck with your weight loss journey, I am sure WE can stop the yo you cycle once and for all.
Hugs,
Ammi