Question: avoiding random point pair with other tiwce.

Hi guys, 

I am in progression of my project. But got stuck in this point, What am i trying to do its create random points in two volume and pick those points to pair them up and try to place a polygon extrusion along the line. 

Q1: after i keep trying, i found out that some of the points join twice with others (eg: A to B , A to D) how to make sure the just join one time?

Is my method of orientating the polygon correct? since i would like to put attraction points that influencing the size of it just on the outside.

sorry for my bad English, hope that u guys understand what I am trying to say.

file is attached so that its more clear.