For one person, saying no to a donut will help them stay on track. For another person, saying yes to a donut without getting anxiety or feeling like a failure will help them stay on track.
Some people struggle with self control - over eating. Some people struggle with food anxiety - not having cake at their birthday in fear of falling off. Progress is measured not only by physical improvements/changes but also mental improvements/changes. If you don't have a healthy mindset FIRST, any physical changes will probably be short lived. Sustainable results only happen with a sustainable mindset.
Let's say you go out and have a high calorie meal. You start to feel anxious the food is there. Take a deep breath. Relax. Enjoy your meal. Get back on track the next day.
Think about it this way, if you are super strict with eating for a month, do you immediately reach your long term fitness goals? Probably not. So this meal probably won't make a huge difference. What you don't want to do is have that high calorie meal every day. It's okay to indulge for a birthday or special event. The more guilty you make yourself feel, the more you will want to punish yourself. The more you will get into binge and purge cycles. Just get back on track the next day or the next meal.
There's more to life than constantly obsessing over losing fat.
They key to weight loss is making LIFESTYLE changes. So any change you make, consider if you can take it on long term.
Question to ask yourself before making a lifestyle change: Do you believe in yourself? Do you believe you can accomplish your fitness goals? What's stopping you? Most of the time it's a mental obstacle.
Motivation is a feeling. It will not last. Progress happens when you take action. Don't give up. Apply for my online training: https://www.surveymonkey.com/r/X7DDR66