Do you have any brothers or sisters?
Do you consider your Christian friends to be brothers and sisters in Christ?
If someone says, “I love God,” but hates a Christian brother or sister, that person is a liar; for if we don’t love people we can see, how can we love God, whom we cannot see?
And he has given us this command: Those who love God must also love their Christian brothers and sisters. (1 John 4:20-21)
It is always harder to understand, to trust something or someone we’ve never seen, than it is with who/what we can see. However we cannot and must not use this as an excuse to not love God to the extent that He desires.
Likewise, if we truly believe in God who we cannot see, we cannot and must not make up any reasons why we cannot love our brothers and sisters in Christ.
However we are only human, so we must ask God to give us understanding and patience in all our relationship so that we can be the kind of person He wants and needs us to be.