It wasn’t wanting to lose weight that helped me changed my eating habits.
Being concerned about my health didn’t make much difference either, despite watching my Dad’s health deteriorate with a poor diet and contribute to his early death.
Wanting to give blood made the difference. My iron levels were too low and that highlighted changes to make for the better, if I wanted to keep donating.
If there’s something you want to do and it’s just not happening, perhaps you need to look for different reasons to get it done. The answer might not be obvious.