What is Love and Why do We Do it?

So we've all heard our fairy tales about love and finding a prince and some ridiculously sexist stories on how the damsel in distress just sits patiently and waits (and sings constantly) for his prince to come and get her the fuck out of the tower so that they can get married and have many babies and live happily ever after even though they've only known the guy for about 18 seconds. Obviously real life isn't like that. Everyone knows that you have to put yourself out there and go through many heartbreaks and many dates before you finally find "The One". Numerous amounts of songs, books, poetry, and art depict this phenomenon called Love.

Some people, however( I won't mention any names * cough* my mom *cough*), don't believe there is such thing.
Isn't that sad?
I've decided to do a little research on the subject and ask the million dollar question: Is there such thing as love? What is love and why do we do it? Is it just a means to procreate and continue the gene? And what is marriage's part in all of this? Is it valid? (Alright well that was about 30 questions but you get the point)

Let's get all technical. 
The technical definition of love has been debated for many years, as it is a very versatile word, though it is only four letters, it can mean a thousand things.
Psychologists consider Love to be a cognitive phenomenon.I will quote a bit on what I found:
" Psychologist Robert Sternberg formulated a triangular theory of love and argued that love has three different components: intimacy, commitment, and passion. Intimacy is a form in which two people share confidences and various details of their personal lives, and is usually shown in friendships and romantic love affairs. Commitment, on the other hand, is the expectation that the relationship is permanent. The last and most common form of love is sexual attraction and passion. Passionate love is shown in infatuation as well as romantic love. All forms of love are viewed as varying combinations of these three components." 
The biological definition says:
"Biological models of sex tend to view love as a mammalian drive, much like hunger or thirst. Helen Fisher, a leading expert in the topic of love, divides the experience of love into three partly overlapping stages: lust, attraction, and attachment. Lust is the feeling of sexual desire; romantic attraction determines what partners mates find attractive and pursue, conserving time and energy by choosing; and attachment involves sharing a home, parental duties, mutual defense, and in humans involves feelings of safety and security. Three distinct neural circuitries, including neurotransmitters, and also three behavioral patterns, are associated with these three romantic styles"


Therefore, in science, what happens is that the brain releases dopamine, pheromones, norepinephrine, and serotonin whenever a certain person is around, creating happiness and excitement. Speaking in evolutionary terms, the body creates a desire to be around this person more often (putting it prudently) in order to create offspring and obviously keep the species alive. 

So then what is all that poetry and all that art and those songs about?
Love is a universal feeling of trust, commitment, and passion for another. Love can be shown in many different forms, from the love between a mother and her children ( most often referred to the truest love of all), the love of friendship and companionship, the love of oneself,etc. But is true romantic love really OBSESSION? what's the difference? Love is the undeniable, excessive need to be constantly thinking and wanting to be around a certain person. So is obsession.