Why does this girl keep walking past me?

Whenever I am at the gym I notice this girl is always walking past me, and for no reason too. Back and forth at least 4 times. It will also be a path that is not even the shortest distance. This last time I noticed she kept walking behind me 3 or 4 times to go to the bathroom and come back. I did notice that her hair was styled different when she came out of the bathroom.

Why does this girl keep walking past me?
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