AForte

I take one Tylenol. It helps me.

I bought some items "in advance" and ended up not wearing them. They either were too big or didn't sit right with my body changes.
I started shopping "just in time" at Value Village and Goodwill stores. They always have a big selection, lot of sizes to try on and very cheap. When you're only wearing sizes for 4 weeks or so, it doesn't makes sense to buy new, even on the clearance rack!
As I started to slow down in my weight loss I found I would stay at a size for longer times and could purchase things in the next size down (if I found an item I liked at a good price). All the while though, I have only been shopping at these "used" clothing stores (though often the items are brand new with tags still on).
Once I'm at goal, I will build a brand new wardrobe with new clothes.
As to the "big girl thinking". I totally get you........
I am now a size 14, but started at a 26-28. Once I started wearing size 18s (and finding them too big half the time), my mind was WARPED. Really? I have been a plus size my entire life (43 yrs old now). I could only shop at 1 store in Canada (Penningtons). There are a few other plus size stores (Addition-Elle, etc.), but they usually only went up to a 22 or a 24, so out of my range.
Now I can shop ANYWHERE! It blows my mind. REALLY! I can even buy Levi's jeans (1st time in my life.....).
Give yourself some time dear. The biggest adjustment with this surgery is not on your body, it is on your mind. You will find the "new you" in body and mind over time.
Enjoy the ride. It's a blast.