We wear the same size 5 to 7 in jeans, and our legs are a similar size too. I am 2 inches taller and I also weight less but yet her thighs don't rub together and mine do! We both are hourglass shape.
Most Helpful Girl
It all has to do with your hips. Do you have small hips? That is probably the issue. It is much easier for someone with wide hips to get a thigh gap. Some people have such wide hips that have a thigh gap even at a heavier weight. Some people with very small hip never have a thigh gap no matter how skinny they get (and thigh gaps have nothing to do with being bow legged. Thigh gaps are when you have a space between your thighs even when your knee's are touching).
An example of wide hips:
Example of small hips:
Karlie Kloss, even though she is extremely skinny she doesn't have a wide thigh gap like other models do.