AutoCAD Inventor :: Maintaining Direction Of A Miter Bisecting Two Lines

I am trying to miter the joints in an assembly being used for iCopy. Currently there is a driver sketch which has lines bisecting each corner at 45 degrees. However, what happens is that when the top line of the sketch is dragged across the bottom line of the sketch or the left line is dragged across the right so that the rectangle inverts itself, the line no longer bisects the angle. See the attached pictures for details.

This sketch shown is a master sketch used to drive part length and end details in an assembly. The blue lines are extruded into surfaces which define the parts using a "Between two planes" extrusion.

The sketch is unconstrained in four ways: overall width, overall height, vertical and horizontal movement. This is done to accomodate its use in as a flexible assembly in an iCopy command. What happens is that when the user applies the iCopy points from the wrong side of a sketch plane in the parent assembly, the sketch flips itself and resizes the assembly but the miters are inverted.