It sounds awfully cheesy, like anything and almost everything related to the topic, but love is the best feeling in the world. It's just a little hard to come by.
It always seemed so easy in the movies, where girl meets boy, boy asks girl out, they talk for a day or a week or so, and somehow, somewhere in the middle, they realize, they're in love. But what we fail to understand or to even see is that movies, dramas, love scenes (the clean and decent romantic ones) are not the whole picture. They are but a fraction of the reality that faces each and everyone of us.
Love, like everything else in this world, relies on two things, the participants' realization and timing. You can spend years, building up for the moment when the other finally realizes that probably, love is there but the most critical thing of all is timing. Sadly, this "timing" can never be planned. I find it to be more of a feeling, provided by the world, the universe, that guides you towards something.
Some people are lucky, that they need not wait long for that push from the universe. Some do not have that sensitivity to hear it and goes on to rely on their realization, which is not all that bad, because eventually, the universe will take over. But still, some wait... and wait... and wait... and eventually, they either feel the timing coming, or they miss it without intending to. Pity, really, for that timing never comes back a second time. It may give a long window period before it leaves, but once it closes, the feeling never goes back and you lose it forever.