Loving God naturally leads to loving your neighbor because God’s love naturally flows outward. God’s love is not a pool, but a spring. Therefore, loving God also means loving others. They are so related in fact that you really can’t separate one from the other. You can’t do one without doing the other. This is what John was teaching in 1 John 4:20-21 (NIV),
Whoever claims to love God yet hates a brother or sister is a liar. For whoever does not love their brother and sister, whom they have seen, cannot love God, whom they have not seen. And he has given us this command: Anyone who loves God must also love their brother and sister.
In other words, if we are experiencing trouble in loving others, the trouble can be traced back to a problem with loving God and/or accepting His love of us, because it is love for God that enables us to love others as He loves us. When love for God is strong and healthy it will show in incarnating that same love we have received to the people around us. Loving others is the fruit of loving God.