It's easy to do, but psychologically tough at first. And that's a good thing.
Stop Purchasing Problems
If you can't stop overeating a certain food, then keep it off your grocery list. Don't purchase what's obviously a problem.
People say that removing something from your diet only makes you want it more. They're right. But maybe that's the psychological struggle you have to overcome in order to learn how to go without it. And it may sound crazy, but you can't eat what's not there. Even if it's on your mind a lot.
This period of going without your favorite snack is a great time to get creative and find alternatives that hit the spot. Do they have to be textbook nutritious? No. You don't have to snack on raw broccoli to lose fat. But they do need to be better than what you were eating. Don't swap your bag of Fritos for Doritos. Try something else that has the main flavor quality you're after.
Is your favorite snack salty? Wrap a couple slices of deli meat around some pepper jack cheese or smear some guac on a rice cake. Many nutrition pros will say these aren't perfect choices. Rice cakes for instance have "empty" calories. But if those 35 empty calories (topped with another 100 calories of something else) can replace the 900 calories of what you were going to eat instead, it's a step in the right direction.
What if your favorite junk food is sweet? Find a sweet alternative. Mix chocolate protein powder with Greek yogurt and a tablespoon of chopped nuts. Or consider an apple. They're okay.
Don't like these suggestions? Not a problem. There's an endless amount of alternatives if you're creative enough and willing to stop spoiling yourself the way mommy and daddy may have done when you lived at home.
Feel Deprived? That's Natural.
Go to the store and walk right past the stuff you over-consume. This goes for alcohol too. Wine has become the cliche indulgence for stressed-out middle aged women, just like beer for men.
So if you're overweight and you drink excessively, abstain for a few months, and then see if you can add a moderate amount back without overdoing it. Yes, it'll suck at first. You'll feel "deprived" but expect that. Embrace it so that there are no surprises.
That's exactly how exercise is. If you're not used to physical effort, working out sucks at first. You feel "deprived" of comfort. But discomfort isn't always a bad thing, and life without it makes us unable to cope with common things that shouldn't be hard. Like avoiding donuts or making it to the gym.
To succeed, you must endure the unpleasant feelings that come along with learning anything new. That's the nature of any form of training. Train yourself to handle these improvements and they'll stop feeling unpleasant. Eventually you'll look forward to all the better alternatives.
Big Warning Here
Avoiding foods you overeat doesn't mean intentionally slashing your caloric intake. That strategy will only make you ravenous and likely to overeat later on. Start with simple (satisfying) swaps and quit paying for things that make you fat.