God is love. Love is the essential nature of God. The very essence of His being is to seek out the best for us. Now we need to know that this is the best based on His wisdom, not on our limited and short-sighted vision.
So if we live in God then we too will love. In every situation, and every relationship, especially the ones with people we don't like, we should be seeking the way of love. Now this is not a way of softness, but of seeking God's best for them, even if we have to pay a price.
If we want to live in love we need to become more and more like Jesus. His life, all of it, is the embodiment if what it means to live in love.
There is no fear in love. Fear has to do with judgement. At the root of all our fears is that God ultimately has it in for us because this is what we deserve. The cross has overturned this. The cross is the basis on which God looks at us, and so He holds nothing against us.
If we know the love of God then we will love our brothers and sisters. It is a nonsense to say that we love God, but then fail to love those whom we can see.