Eating is a balance of moderation and variation not deprivation.
A good diet is one of 3 keys to living a healthy lifestyle; the others are sleep and exercise. Creating healthy habits are the keys to making them work for you. When you establish an overall pattern of healthful nutrition and a salubrious lifestyle, your body and brain will thank you.
I typically approach eating with an 80/20 ratio and have flexibility built in. For instance, 80% of the time I embrace healthy eating while 20% of the time I treat myself, without regret. Depending upon several factors (life, celebrations, health or illness), that ratio fluctuates based upon your needs. The key is determining what works best for you and allow for flexibility and change.
A big part of creating these healthy habits is learning to not punish yourself when you enjoy cake, cookies, pizza or fries. Eat it, savor it and move on. Jump back into your healthy ratio and forgeddaboutit! Life is way too short to beat yourself up over it. The biggest joy is finding the balance that works and fits your lifestyle.
This is part of what I teach clients in my 8 Step Nutrition Program. Want to learn more? You can find the program here: https://thewholefoodnut.com/8-step-nutrition-program/