Excellent observation...yes! That must be how river's change their course. Oooh that's a great sentence eh? 'change your course'. mmmm! Rushing water floods the banks and verges off the main riverbed into some new territory! Yay! Maybe this is where your grief and wound have taken you...you've jumped out of the river you were in before and are on a new course (because of the flowing emotions...releasing...)
Do you really have a Twin sister?? (I guess so!)
Ah! Interesting dream....that you are hanging on to this old, wornout nightie! The message has got to be: let go, let go! Something far more beautiful and wondrous will take it's place...