Some people don't know how to fall in love, like not knowing how to swim. They panic first when they jump in. Then they figure it out.
That's the fairy tale. You meet, you fall in love, you kiss, and neither of you is revolted by it. You get married and have kids and live happily ever after.
People fall in love all the time. And it's not always with the right people. And it's not always reciprocated.