It happens way to often in the Christian world. There is relational breakdown between believers that is not addressed.
It may be an offence committed by one party that they are not even aware of but it is held against them by another. It may be disagreements over strategy or philosophy that causes one to marginalize the other. In many cases it actually has no root in reality but one party makes assumptions about the other party and never bothers to clarify whether those assumptions are indeed correct.
No matter the cause, such relational breakdown has an impact that goes beyond the two who don't understand each other. Because of one or both parties mistrust, others around them are infected by the mistrust because it is very hard to hide one's attitude toward another. That means that relational breakdown impacts the ministry that we are a part of. It is not a victimless sin.
The Apostle Paul encourages us to live at peace with one another as much as it is possible. In other words, when we become aware of relational breakdown it is our responsibility to try to address it whether we were the cause or not.
Our unwillingness to try to bring peace is harmful to the work of God and may in fact be sinful on our part. To hold grudges or live with relational breakdown and not have tried to bridge the gap is one of the common but unfortunate tendencies of our lower nature. We have all been guilty at one time or another. Part of spiritual maturity is learning to proactively try to bridge the gap when we become aware of one.
The most obvious step to bridging relational gaps is to start with a conversation. Many assumptions we make about others are wrong. A pastor may assume motives about a board member who challenges him or a team member about another team member.
My experience is that my assumptions about poor motives have almost always been wrong! Because I assumed poor motives I then caused a wall to go up in my own mind about the other. In such cases, it is our fault for the relational disconnect. The other party may in fact be clueless that there is even an issue.
Often, if we are willing to probe and try to understand the other's heart we find out that not only are there not poor motives but we actually want the same thing - but have been misunderstanding one another. Asking questions while not assuming motives or being judgemental can at least get the issues on the table. Unless they are on the table there is no means of dealing with them.
Where the issues are thorny it may be necessary to have a series of conversations or to bring a neutral party into the discussion to seek understanding.
Not all relational disconnects can be resolved because it takes two to want resolution. Most can, if one of the parties will press into the disconnect, acknowledge that it is there and seek to bridge the gap. Even if they know that they were not the cause, a mature individual will seek to resolve it and will not ignore it.
Taking the step of resolution is not always easy. But relational breakdowns are dangerous to a church or ministry organization. That danger ought to outweigh our fear of confronting it. Often we will find that the other party is relieved to solve it.