Hi GT,
We have a natural heart and a spiritual heart, our natural heart is at the center of our body, keeps the blood flowing to keep our body alive, and our spiritual heart which is where Christ by the Spirit dwells once we are born of God, is the centre of our being, and the blood of Christ keeps the body of Christ alive.
Our spiritual heart is where we love, care and show forgiveness and mercy from, and we can also show hardness and hatred from, but Christ in our hearts through the Holy Spirit will help us to overcome the wrong that is within us, if we are willing to do the will of God and obey him.
That warm feeling of love doesn't come from our natural heart does it? It's comes from the heart of us, from within our very being.