'What happened, I thought they hated each other?'
'It's just like musical chairs, the music stopped and they were the only ones left standing.'
Sex in the City 2

'It was not exactly love at first sight. But it turns out, it was love, she was the first girl to accept him for the man that he actually is.'
Sex in the City 2

(Ok the quotes end here)
The series is actually a lot like a movie. Pretend its all a movie. In the beginning she has a simply man a guy that she "loves" and who is perfect for her. And then she meets his brother and at the beginning she isn't really into him, but the more time she spends with him the more she grows attracted to him. At the end she will end up with him.