Like everyone else said, planning is key, but if I'm honest, I get sick of planning sometimes.
I completely understand where you are coming from, I've been there plenty of times, and I've found myself doing the same kind of thing a few weeks ago.
Apart from what others have suggested, the only thing I can suggest is to make sure you plan some sort of treats into your week. Maybe plan to have some sort of fakeaway on a Friday night, or actually go out somewhere during the week/weekend for a meal or drinks.
Don't avoid using your syns, make sure you use them. You don't have to use all of them, just make sure you use some. Whether it's a bag of crisps, or bar of chocolate, or sauces with meals. Throw them into your day somewhere.
Good luck hun, we're all here for you if you need us