Read Matthew 18:15-20
15 “If your brother sins against you,r go to him and show him his fault. But do it privately, just between yourselves. If he listens to you, you have won your brother back. 16But if he will not listen to you, take one or two other persons with you, so that ‘every accusation may be upheld by the testimony of two or more witnesses,’ as the scripture says. 17And if he will not listen to them, then tell the whole thing to the church. Finally, if he will not listen to the church, treat him as though he were a pagan or a tax collector.
18 “And so I tell all of you: what you prohibit on earth will be prohibited in heaven, and what you permit on earth will be permitted in heaven.
19 “And I tell you more: whenever two of you on earth agree about anything you pray for, it will be done for you by my Father in heaven. 20For where two or three come together in my name, I am there with them.”
Just before this passage Jesus tells his disciples about the man who loses one sheep and goes out looking for it. In Christian relationships we are to make every effort toward reconciliation; where separation is inevitable it has to be handled prayerfully.
Pray for unity in your church.