On the Nature of LOVE

We humans try to attain perfection in everything. Say if we have a job in a firm, we try to go for a better firm which may be giving us a better paycheck or a better job profile. If say we are an author then first I start with a small publisher but then if my work is really good and appreciated then I look for bigger names to publish my work. Why ??
Because that is rational, If I am really good I should try to attain my potential to the fullest extent. Again for objective or some may say materialistic things too we try to attain the things which are better than the things we have, like a better Car, a bigger house etc etc. Here too we try to attain the highest we can achieve BUT yes here comes the BUT. Why do we compromise when it comes to emotions and the the greatest of all emotions LOVE.

Yes, if at a point of time we have girlfriend/boyfriend and meet somebody new, whom we know from the core of our heart would be better for us ( it is just not the other person is more beautiful or say has a better bank balance, successful etc etc, but the whole thing; I hope you understand) but we still persist and why ??!! Shouldn't we try to attain perfection here too ??! Why double standards ?? We make our selves believe that the person with which we are now is the best, putting a veil of ignorance on our eyes or even worse; we think "what will my present partner feel, no no I can't hurt her/him". Hey, do we feel bad for the firm we leave to join another or for the shopkeeper whose shop we have stopped visiting since Reliance Fresh opened in my locality ??!
No !! Then why for the case when it deals with human emotions. Why can't we think every thing as an object, If the person I am leaving is really a rational being she/he will understand and herself/himself look for their soul mate. I believe every person has a soul mate and it is up to us to find, most of us don't so we die dis-satisfied.
On this nature of love even Rabindranath Tagore has written a poem. The nature is such that one we get we say him/her to be the one but we just don't know how many better were and are there still waiting.

On the Nature of Love

The night is black and the forest has no end;
a million people thread it in a million ways.
We have trysts to keep in the darkness, but where
or with whom - of that we are unaware.
But we have this faith - that a lifetime's bliss
will appear any minute, with a smile upon its lips.
Scents, touches, sounds, snatches of songs
brush us, pass us, give us delightful shocks.
Then peradventure there's a flash of lightning:
whomever I see that instant I fall in love with.
I call that person and cry: `This life is blest!
for your sake such miles have I traversed!'
All those others who came close and moved off
in the darkness - I don't know if they exist or not.

But Yes after all this radical thoughts at times I get confused. If what I said is true then for how long should I continue the pursuit for the one. And If I don't find that person. And then if others don't understand and the people whom I leave are emotionally weak. It is not that I did not love them but I out grew them and moved on. But will they understand. Because life is not "Atlas Shrugged". What about the institution of marriage. So what should I do torn between my principles , ideology and emotions.
Today I am confused, hope I get the answer one day.......