You did not fail. Dieting failed you. Even though the U.S. weight loss industry has grown to almost $59 BILLION annually, chronic disease statistics have not improved and over 90% of dieters experience weight regain (Bacon and Aphramor 2011).
Short-term weight loss lures us into thinking that food restriction is the answer to long-term weight loss. Someone says, "I lost 17 pounds this month" and everyone cheers. But weight loss through restriction only causes weight-cycling (a.k.a. yo-yo dieting). So, what's wrong with that? Not only does it negatively impact your thinking ("I failed again"), weight cycling increases your risk of high blood pressure, diabetes, and high cholesterol while promoting inflammation in your body.
On the other hand, people who are dieting often see benefits in the short run, such as more energy and decreased pain. However, is it weight loss (alone) causing those benefits OR is it the increase in nutrient-dense foods (a.k.a. more vegetables and fruit) with a decrease in sugar-filled processed food?
In fact, research shows changing the types of foods you eat is one of the reasons for improved health. People can eat healthier foods and increase their physical activity - and without losing weight - decrease their risk of disease (Ikeda et al. 2005).
Much of the research around "non-diet healthy eating" is with Intuitive Eating. The focus of Intuitive Eating is listening to your body's cues about eating, re-building trust that your body will tell you what it needs, when it needs it, and how much it needs. We all did this as young children.
Also, with Intuitive Eating you learn to address feelings and life-issues without the use of food as a fake-comforter.
The results of Intuitive Eating? Research shows that you actually choose more nutritious foods and you don't gain weight. If your body needs to lose weight, it will over time (Bacon 2011; Tribole & Resch 2012).
Stop blaming yourself. Stop dieting. Start Intuitively Eating.
(The research cited is derived from ACE Fitness Journal May 2018 "Health at Every Size")