let me know.

How do you define a 'free' day or week? Eating what you want in the quantity you want? With or without logging it?

I log everything I eat, on regular days and 'splurge' days (e.g. Christmas) and anything in between.
I aim to stay within my calorie goal on most days, sometimes going up to maintenance calories and occasionally over maintenance for special occasions. As long as I'm overall in a deficit, it's fine.
And within those calories I eat all the foods I like:
- in more appropriate quantities
- and slightly different proportions than before, because I'm mindful of what satiates me
My habits were pretty balanced to begin with, so it's not a big change, just gradual improvements. I've never 'fallen off the wagon', since I've never excluded any foods from my diet. But being more conscious of the caloric values of the foods I eat and whether or not they satiate me, has lead me to make slightly different choices.

If you eat a lot of junk food now, I would suggest not giving it all up in one go. Build better habits gradually. Start by eating the same foods as before but within your calorie goal. For your higher calorie items, see if you can find a similar food that has less calories and leaves you feeling fuller (more fiber and protein is often a good way). Experiment and tweak how you eat to find a way of eating that you like and leaves you satisfied.
The all or nothing approach, as you've seen yourself, rarely leads to lasting changes.

Edit: I'd like to add that being very restrictive is not a good idea where food choices are concerned, but also with regards to how many calories you allow yourself to consume. If you choose a very aggressive rate of loss and therefore have a low calorie goal, it's more likely that you won't be able to stick with it and give up.