It is absolutely possible. I started this journey in 2011, the year I turned 40, after years of binging and years of steadily gaining weight. Is it "easy" now? No. Do I still binge sometimes? Yes. Do I still lose control? Yes.
But - 3 years later - I am still maintaining my weight loss. The more success I have, which for me (now) is maintaining and losing the holiday/vacation weight when I gain it, the more natural it becomes. It is not "easy" - but it is more natural. I am starting to think more like a healthy-weight person.
I have to admit, I went nuts over the holidays. I totally lost control and I felt guilty and full of shame at times. But, I was able to forgive myself and start over, it's the only thing I could do. I can't go back in time and
not eat 50 Christmas cookies in one day, I just had to learn from it and remember how mentally and physically awful it felt.
Yeah, it sucks re-losing the weight I already lost, but the only alternative is not to lose it again or to continue gaining. Until a time machine is invented...