Majnun may love Layla, but he is not in love with her. He is in love with the feeling of loving her. He’s in love with the passion and strength of his love. He prays to let his love for her grow and be with him forever. He doesn’t pray to have her and be with her forever. This looks pathetic to pretty much anyone. But I believe that some people want to suffer. If he suffers from his yearning, and he wants to suffer from his love, then he is doing what he wants to, what he enjoys. Doing what you want in life is not pathetic. He could have let go and marry another girl with black hair, but he knew that wouldn’t make him happy.
We may not be able to understand but maybe he just doesn’t want we strive for in life. Some people aren’t satisfied with traditional happiness, so they do not want it, because people always seek satisfaction in life, even if that satisfaction is in suffering. I think Layla was this way too. He would be “pathetic” if he was actually in love with just Layla and not the feeling of love, because then he spent his whole life suffering for his love when what he loves is Layla, not the feeling of love.
According to Socrates, love is a yearning. You cannot love what you already have. If happiness is getting what you want, and what you want is love, you can never be happy and in love.