Of course it isn't. From a Christian's point of view it is a reasonable position to say that since God created us He is the source of the goodness that is in us. It is said mankind was created in the image of God therefore we will share some of the characteristics of God.

It would really only be a reasonable position if humans were created by God as they are now, rather than having evolved to be as we are. Chimpanzees, for example, show the ability to do caring things, admittedly in much more rudimentary form - but that's what you'd expect.  Humans exhibit a more developed form of this, having greater ability to put themselves in another's place and imagine how it must feel to be them, but they are not completely unique in this, just more highly developed.  The idea, therefore, that humanity was somehow chosen above the animals, by an external entity, God, to bear 'his' divine imprint, is brought into question. As a proposal, it doesn't really fit many of the facts, and it is certainly superfluous as an explanation for the existence of Love. It's rather like saying we have legs because God has legs. We can show why we have evolved legs, and we have no evidence to show that there is an external God with legs.