real world logic vs. personal logic

I often wonder why it is that most people that i encounter on a daily basis appear to tackle certain issues in a manner that most of society would consider logical, even rational, and yet, for the life of them, choose illogical, completely irrational ways of thought to describe others, even if the consequences of that choice are fully known to be negative.
For example, lets say at some point we choose a person to associate with based on a first impression that appeals to our sense of sight. Very pretty, or very handsome, whatever the case may be. As time goes by, we discover that, although they are pleasant on the outside, their personality may be irritating, even dangerous, to us. Let us say that this individual would constantly put us in the middle of a domestic dispute that is not our own, but for lack of a character witness, the audience they choose is you, because they believe that you are objective.
keep in mind that they each feel this way torwards you, yet maintain that your objectivity only applies to the individual.
Based on the level of discomfort you feel at that very moment, would it be logical, and sound rationality, to continue to associate with these individuals considering your first impression?
No, it is not. And yet, we find ourselves being victimized by the very cliches that have molded most of our society: well, she is a knock-out!
but he's so hot!
c'mon, shes sexy, so she cant be all bad!
but if i dump him, i'll never find better!
Do you see what i mean? First our assumption is logical... Physical attraction is a tell-tale sign that two people just might end up together. Okay, but then when things turn sour, its never considered okay to drop a sexy person in favor of one less so, even if the less sexy person has a heart of gold. Why? for fear of never finding better? Doubtful. But for fear of losing face with our peers is exactly the reason we engage in this controlled insanity. But we never admit that, because we do not wish to be viewed as weak and indesisive to our friends and family. it never occurs to us that the object of our very vanity in choosing in such a chaotic fashion degrades us to others because we forget at the moment how tranparent we really are to those who know us. And yet, we think of ourselves as academy award winning actors who never get caught" out of role" so to speak, and when we are confronted with the facts, we dont see the root cause, which is our personal relationships, yet find all kinds of time to degrade those of out critics who have relationships. Transference of responibilty, people. Anything but us. And we sit back and wonder why our society seems to have no wholesome values, no respect for each other, and total disregard for our individual lives. They cant have what we dont teach! And we resist teaching them! Because if we teach them responsibility, we must also show it, and it seems to constricting to society to ever be bound by ones own laws. Everyone else...YES. Ourselves.... oh, heavens, NO!