I hear you! I am 4 weeks post op now and I have 2 mantras: "I'M NEVER GOING BACK!" and "IT's JUST NOT WORTH IT!" (when tempted to taste or take a bit of something not allowed.) This is way too much work, money, and risk to throw it away. Use this pre-op time to really clean up your eating. After surgery, you want every bite to be as nutritionally dense as possible, and as healthy as possible. The "New you" deserves nothing less. Get rid of the artificial sweeteners, colors and flavorings. Get rid of the soda and caffeine. (Caffeine may come back later, but you may find you feel better and more stable without it and really not want it anymore. I LOVED coffee, but can't even stomach the thought of it now!) Absolutely get rid of the sugar! ALL sugar! Get rid of processed food. Cook it yourself. Get rid of simple carbs/starches. Minimize wheat or get rid of it altogether. Learn to enjoy other whole grains like quinoa, brown rice, millet, teff, amaranth. Learn to enjoy veggies - LOTS of veggies! They will be the life saver of you success. Of course, get rid of alcohol and tobacco.
If you can start making these lifestyle changes NOW, you will have a much easier time after surgery. Recovery is hard enough without having to cold turkey off addictions like sugar and caffeine. Use this time to really EMBRACE the changes. Each change you make means you "WILL NEVER GO BACK!"
As far as temptations go, yes they are there, but..... "IT'S JUST NOT WORTH IT!" I had to fix a full Mexican meal for a family party, make muffins for work, and cake for a birthday party. I did take a couple of tiny tastes to check for seasoning, but then I spit them out. I remind myself that my time will come to have some of these things, but not right now. Each choice you make is a choice to "go back" or "never go back."
Remember that a slip up one day is a mistake. A slip up 2 days in a row is called RELAPSE. Just get back on board immediately.
I found that keeping my food journal is critical. I plan all my meals (as tiny as they are) the day before, so there is no guess work the next day.
We got ourselves where we are by a lot of bad choices over a long time. (Even if we thought they were good choices at the time with the dieting, starvation, and other crazy stuff we did to wreck our metabolisms and disrupt the normal hormone pathways.) It will take a lot of GOOD choices to rewire our brains and reframe our thinking about food - what is wonderful (veggies) and what is poison (sweets and simple carbs.) We can do it! Let your OCD and rules work for you!!!!!