Love that is only felt in the heart, is not truly love. That is just an emotion and emotion in itself is not worth much -- it must have action to place worth on that emotion (either for the good or the bad). If a man says that he loves his children, but gets drunk and beats them every night, that is not the right action that goes with love, and therefore his "love" is not worth anything. If a woman says that she loves God, but refuses to obey His commands, then that love is also not worth anything, since Jesus said, "if you love me you will obey my commands".
Also, we must love that is which is supposed to be loved, and not that which is supposed to be hated. For example, what value do we place on it if someone loves murder? That is not a good thing to love. What value would we place on it if someone loved sexual perversion? To make it clear, a love of something that is evil, is likewise a hatred for something which is good. Hence, action must be attached to the emotion and the emotion must be directed toward what is right.
Thus, we would be wrong to say that "love" alone is always a good thing. Even the two greatest commandments tell us exactly what to love, and how to love. Let us work toward having a godly form of love, and make sure that we are loving that is which is good and right. Love alone is only an emotion, it is the deed, the works, the actions that go along with love that will determine if it is a love that God will accept.