At first, love comes from you as a whole. That you almost love nothing else but yourself because other people, especially your parents, are telling you to love yourself first.
But as time goes by, you easily learn to love others. They tell you that they care for you and that they love you. So, you give your love in return.
In the end, you always give them your love to the best that you can. Suddenly, you almost forget to love yourself. You forget to leave some part of “love” which you have reserved for yourself. It’s just that it is too late now to retrieve what you have lost. It is also too late now for you to realize, that sooner or later, you will only have nothing left but an empty heart.