I think horses need mirrors attached to saddles though. We stopped for awhile and I was no longer sitting center and her backbone by my hip. The owner looked at her and laughed. She told me she was standing on 3 feet and leaning:')
Eventually you will be able to feel where her feet are, it just takes time and riding. Sometime when you're comfortable with being bareback and your trainer is with you, put your toe up in SL's leg where it meets her body - not hard though. She should start limping. I used to do that years ago to get my cousin to turn around and start home. She'd ride through the night if she could and after several hours, I was ready to quit.