Not ready on time card

Well she is now playing the not ready on time card !!
I drive 200 miles on a Friday to see my son. (after working a full day)
I then check into a hotel go shopping for what we need for the weekend.
I pick him up about 6:30 or 7:00
She has now decided I will only see him every other weekend, So why on the weekend I see him is she handing him over at 10 pm ?
Day is gone. Time for bed.
Why is she getting away with it ?
Law dont seem to be on my side.