I will add this...it may or may not apply, here.....
some aspects between two people are "chemistry"...or, even spiritual....
It is either there...or, it isn't...
and, it can not be seen by the naked eye...and, it isn't represented on print outs or financial tabulations.....
It is hard to explain or even pin down...but, I believe that it exists...at least, it has for me....