Lasting Habits, Lasting Health

For a long time now, I’ve been trying to get healthy and lose weight. I’ve struggled with my weight on and off since middle school, and no matter how many diets and exercise plans I try, I can never get them to stick. I’m guilty of trying fad diets, sure, but I’ve also tried some really straightforward ones that involve calorie-counting and basic stuff like that. But, still, nothing works! Experts, can you help me? How can I get good at eating right and exercising – and not just relapse after a short time?