What is love?

After finishing the documentary of Derrida I found the most interesting part to be when Derrida was asked to talk about "love". He immediatly refuses to do so and says he has nothing to say about "love" because that topic is too general. He explains he has an "empty head of love", and the reason why so many philosophers speak of it is because of all the confusion that comes from it. This is when Derrida explains his perspective on the subject. He cannot decide whether we love someone for who they are, or because of the certain characteristics that make up that someone. He says he is divided between "the who and the what". However, he then explains that there are narcissists, people who are in love with themselves. For most it is as you mature from child to adulthood that you slowly change your narcissitic ways and realize the importance of a good balance between the love and attention you give yourself and others. But when we have fallen in love with another person is it that person as a whole that we have fallen in love with or is it our narcissitic ways that make us love just certain aspects?