I don't understand this

I was just watching a commercial about a chick who was so excited to have lost so much weight that she was now a size 2. ???? I spent most of my adult life trying to make it from a size 2 to a size 6. So now I'm almost 62 yrs. old, and I finally look like an adult woman, wear a size 8, have boobs and a butt and clock in at 120 lbs. Can't tell you how happy I am. I just don't get it.